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The High Frontier, Redux

(I am currently suffering from a bad cold, and it's screwing with my ability to think straight. So rather than risk damaging my real work in progress, I decided to tidy up some thoughts I've been kicking around for a while, and bolt together this essay. Which will, I hope, begin to highlight the problems I face in trying to write believable science fiction about space colonization.)

I write SF for a living. Possibly because of this, folks seem to think I ought to be an enthusiastic proponent of space exploration and space colonization. Space exploration? Yep, that's a fair cop — I'm all in favour of advancing the scientific enterprise. But actual space colonisation is another matter entirely, and those of a sensitive (or optimistic) disposition might want to stop reading right now ...

I'm going to take it as read that the idea of space colonization isn't unfamiliar; domed cities on Mars, orbiting cylindrical space habitats a la J. D. Bernal or Gerard K. O'Neill, that sort of thing. Generation ships that take hundreds of years to ferry colonists out to other star systems where — as we are now discovering — there are profusions of planets to explore.

And I don't want to spend much time talking about the unspoken ideological underpinnings of the urge to space colonization, other than to point out that they're there, that the case for space colonization isn't usually presented as an economic enterprise so much as a quasi-religious one. "We can't afford to keep all our eggs in one basket" isn't so much a justification as an appeal to sentimentality, for in the hypothetical case of a planet-trashing catastrophe, we (who currently inhabit the surface of the Earth) are dead anyway. The future extinction of the human species cannot affect you if you are already dead: strictly speaking, it should be of no personal concern.

Historically, crossing oceans and setting up farmsteads on new lands conveniently stripped of indigenous inhabitants by disease has been a cost-effective proposition. But the scale factor involved in space travel is strongly counter-intuitive.

Here's a handy metaphor: let's approximate one astronomical unit — the distance between the Earth and the sun, roughly 150 million kilometres, or 600 times the distance from the Earth to the Moon — to one centimetre. Got that? 1AU = 1cm. (You may want to get hold of a ruler to follow through with this one.)

The solar system is conveniently small. Neptune, the outermost planet in our solar system, orbits the sun at a distance of almost exactly 30AU, or 30 centimetres — one foot (in imperial units). Giant Jupiter is 5.46 AU out from the sun, almost exactly two inches (in old money).

We've sent space probes to Jupiter; they take two and a half years to get there if we send them on a straight Hohmann transfer orbit, but we can get there a bit faster using some fancy orbital mechanics. Neptune is still a stretch — only one spacecraft, Voyager 2, has made it out there so far. Its journey time was 12 years, and it wasn't stopping. (It's now on its way out into interstellar space, having passed the heliopause some years ago.)

The Kuiper belt, domain of icy wandering dwarf planets like Pluto and Eris, extends perhaps another 30AU, before merging into the much more tenuous Hills cloud and Oort cloud, domain of loosely coupled long-period comets.

Now for the first scale shock: using our handy metaphor the Kuiper belt is perhaps a metre in diameter. The Oort cloud, in contrast, is as much as 50,000 AU in radius — its outer edge lies half a kilometre away.

Got that? Our planetary solar system is 30 centimetres, roughly a foot, in radius. But to get to the edge of the Oort cloud, you have to go half a kilometre, roughly a third of a mile.

Next on our tour is Proxima Centauri, our nearest star. (There might be a brown dwarf or two lurking unseen in the icy depths beyond the Oort cloud, but if we've spotted one, I'm unaware of it.) Proxima Centauri is 4.22 light years away.A light year is 63.2 x 103 AU, or 9.46 x 1012 Km. So Proxima Centauri, at 267,000 AU, is just under two and a third kilometres, or two miles (in old money) away from us.

But Proxima Centauri is a poor choice, if we're looking for habitable real estate. While exoplanets are apparently common as muck, terrestrial planets are harder to find; Gliese 581c, the first such to be detected (and it looks like a pretty weird one, at that), is roughly 20.4 light years away, or using our metaphor, about ten miles.

Try to get a handle on this: it takes us 2-5 years to travel two inches. But the proponents of interstellar travel are talking about journeys of ten miles. That's the first point I want to get across: that if the distances involved in interplanetary travel are enormous, and the travel times fit to rival the first Australian settlers, then the distances and times involved in interstellar travel are mind-numbing.

This is not to say that interstellar travel is impossible; quite the contrary. But to do so effectively you need either (a) outrageous amounts of cheap energy, or (b) highly efficient robot probes, or (c) a magic wand. And in the absence of (c) you're not going to get any news back from the other end in less than decades. Even if (a) is achievable, or by means of (b) we can send self-replicating factories and have them turn distant solar systems into hives of industry, and more speculatively find some way to transmit human beings there, they are going to have zero net economic impact on our circumstances (except insofar as sending them out costs us money).

What do I mean by outrageous amounts of cheap energy?

Let's postulate that in the future, it will be possible to wave a magic wand and construct a camping kit that encapsulates all the necessary technologies and information to rebuild a human civilization capable of eventually sending out interstellar colonization missions — a bunch of self-replicating, self-repairing robotic hardware, and a downloadable copy of the sum total of human knowledge to date. Let's also be generous and throw in a closed-circuit life support system capable of keeping a human occupant alive indefinitely, for many years at a stretch, with zero failures and losses, and capable where necessary of providing medical intervention. Let's throw in a willing astronaut (the fool!) and stick them inside this assembly. It's going to be pretty boring in there, but I think we can conceive of our minimal manned interstellar mission as being about the size and mass of a Mercury capsule. And I'm going to nail a target to the barn door and call it 2000kg in total.

(Of course we can cut corners, but I've already invoked self-replicating robotic factories and closed-cycle life support systems, and those are close enough to magic wands as it is. I'm going to deliberately ignore more speculative technologies such as starwisps, mind transfer, or AIs sufficiently powerful to operate autonomously — although I used them shamelessly in my novel Accelerando. What I'm trying to do here is come up with a useful metaphor for the energy budget realistically required for interstellar flight.)

Incidentally, a probe massing 1-2 tons with an astronaut on top is a bit implausible, but a 1-2 ton probe could conceivably carry enough robotic instrumentation to do useful research, plus a laser powerful enough to punch a signal home, and maybe even that shrink-wrapped military/industrial complex in a tin can that would allow it to build something useful at the other end. Anything much smaller, though, isn't going to be able to transmit its findings to us — at least, not without some breakthroughs in communication technology that haven't shown up so far.

Now, let's say we want to deliver our canned monkey to Proxima Centauri within its own lifetime. We're sending them on a one-way trip, so a 42 year flight time isn't unreasonable. (Their job is to supervise the machinery as it unpacks itself and begins to brew up a bunch of new colonists using an artificial uterus. Okay?) This means they need to achieve a mean cruise speed of 10% of the speed of light. They then need to decelerate at the other end. At 10% of c relativistic effects are minor — there's going to be time dilation, but it'll be on the order of hours or days over the duration of the 42-year voyage. So we need to accelerate our astronaut to 30,000,000 metres per second, and decelerate them at the other end. Cheating and using Newton's laws of motion, the kinetic energy acquired by acceleration is 9 x 1017 Joules, so we can call it 2 x 1018 Joules in round numbers for the entire trip. NB: This assumes that the propulsion system in use is 100% efficient at converting energy into momentum, that there are no losses from friction with the interstellar medium, and that the propulsion source is external — that is, there's no need to take reaction mass along en route. So this is a lower bound on the energy cost of transporting our Mercury-capsule sized expedition to Proxima Centauri in less than a lifetime.

To put this figure in perspective, the total conversion of one kilogram of mass into energy yields 9 x 1016 Joules. (Which one of my sources informs me, is about equivalent to 21.6 megatons in thermonuclear explosive yield). So we require the equivalent energy output to 400 megatons of nuclear armageddon in order to move a capsule of about the gross weight of a fully loaded Volvo V70 automobile to Proxima Centauri in less than a human lifetime. That's the same as the yield of the entire US Minuteman III ICBM force.

For a less explosive reference point, our entire planetary economy runs on roughly 4 terawatts of electricity (4 x 1012 watts). So it would take our total planetary electricity production for a period of half a million seconds — roughly 5 days — to supply the necessary va-va-voom.

But to bring this back to earth with a bump, let me just remind you that this probe is so implausibly efficient that it's veering back into "magic wand" territory. I've tap-danced past a 100% efficient power transmission system capable of operating across interstellar distances with pinpoint precision and no conversion losses, and that allows the spacecraft on the receiving end to convert power directly into momentum. This is not exactly like any power transmission system that anyone's built to this date, and I'm not sure I can see where it's coming from.

Our one astronaut, 10% of c mission approximates well to an unmanned flight, but what about longer-term expeditions? Generation ships are a staple of SF; they're slow (probably under 1% of c) and they carry a self-sufficient city-state. The crew who set off won't live to see their destination (the flight time to Proxima Centauri at 1% of c is about 420 years), but the vague hope is that someone will. Leaving aside our lack of a proven track record at building social institutions that are stable across time periods greatly in excess of a human lifespan, using a generation ship probably doesn't do much for our energy budget problem either. A society of human beings are likely to need more space and raw material to do stuff with while in flight; sticking a solitary explorer in a tin can for forty-something years is merely cruel and unusual, but doing it to an entire city for several centuries probably qualifies as a crime against humanity. We therefore need to relax the mass constraint. Assuming the same super-efficient life support as our solitary explorer, we might postulate that each colonist requires ten tons of structural mass to move around in. (About the same as a large trailer home. For life.) We've cut the peak velocity by an order of magnitude, but we've increased the payload requirement by an order of magnitude per passenger — and we need enough passengers to make a stable society fly. I'd guess a sensible lower number would be on the order of 200 people, the size of a prehistoric primate troupe. (Genetic diversity? I'm going to assume we can hand-wave around that by packing some deep-frozen sperm and ova, or frozen embryos, for later reuse.) By the time we work up to a minimal generation ship (and how minimal can we get, confining 200 human beings in an object weighing aout 2000 tons, for roughly the same period of time that has elapsed since the Plymouth colony landed in what was later to become Massachusetts?) we're actually requiring much more energy than our solitary high-speed explorer.

And remember, this is only what it takes to go to Proxima Centauri our nearest neighbour. Gliese 581c is five times as far away. Planets that are already habitable insofar as they orbit inside the habitable zone of their star, possess free oxygen in their atmosphere, and have a mass, surface gravity and escape velocity that are not too forbidding, are likely to be somewhat rarer. (And if there is free oxygen in the atmosphere on a planet, that implies something else — the presence of pre-existing photosynthetic life, a carbon cycle, and a bunch of other stuff that could well unleash a big can of whoop-ass on an unprimed human immune system. The question of how we might interact with alien biologies is an order of magnitude bigger and more complex than the question of how we might get there — and the preliminary outlook is rather forbidding.)

The long and the short of what I'm trying to get across is quite simply that, in the absence of technology indistinguishable from magic — magic tech that, furthermore, does things that from today's perspective appear to play fast and loose with the laws of physics — interstellar travel for human beings is near-as-dammit a non-starter. And while I won't rule out the possibility of such seemingly-magical technology appearing at some time in the future, the conclusion I draw as a science fiction writer is that if interstellar colonization ever happens, it will not follow the pattern of historical colonization drives that are followed by mass emigration and trade between the colonies and the old home soil.

What about our own solar system?

After contemplating the vastness of interstellar space, our own solar system looks almost comfortingly accessible at first. Exploring our own solar system is a no-brainer: we can do it, we are doing it, and interplanetary exploration is probably going to be seen as one of the great scientific undertakings of the late 20th and early 21st century, when the history books get written.

But when we start examining the prospects for interplanetary colonization things turn gloomy again.

Bluntly, we're not going to get there by rocket ship.

Optimistic projects suggest that it should be possible, with the low cost rockets currently under development, to maintain a Lunar presence for a transportation cost of roughly $15,000 per kilogram. Some extreme projections suggest that if the cost can be cut to roughly triple the cost of fuel and oxidizer (meaning, the spacecraft concerned will be both largely reusable and very cheap) then we might even get as low as $165/kilogram to the lunar surface. At that price, sending a 100Kg astronaut to Moon Base One looks as if it ought to cost not much more than a first-class return air fare from the UK to New Zealand ... except that such a price estimate is hogwash. We primates have certain failure modes, and one of them that must not be underestimated is our tendency to irreversibly malfunction when exposed to climactic extremes of temperature, pressure, and partial pressure of oxygen. While the amount of oxygen, water, and food a human consumes per day doesn't sound all that serious — it probably totals roughly ten kilograms, if you economize and recycle the washing-up water — the amount of parasitic weight you need to keep the monkey from blowing out is measured in tons. A Russian Orlan-M space suit (which, some would say, is better than anything NASA has come up with over the years — take heed of the pre-breathe time requirements!) weighs 112 kilograms, which pretty much puts a floor on our infrastructure requirements. An actual habitat would need to mass a whole lot more. Even at $165/kilogram, that's going to add up to a very hefty excess baggage charge on that notional first class air fare to New Zealand — and I think the $165/kg figure is in any case highly unrealistic; even the authors of the article I cited thought $2000/kg was a bit more reasonable.

Whichever way you cut it, sending a single tourist to the moon is going to cost not less than $50,000 — and a more realistic figure, for a mature reusable, cheap, rocket-based lunar transport cycle is more like $1M. And that's before you factor in the price of bringing them back ...

The moon is about 1.3 light seconds away. If we want to go panning the (metaphorical) rivers for gold, we'd do better to send teleoperator-controlled robots; it's close enough that we can control them directly, and far enough away that the cost of transporting food and creature comforts for human explorers is astronomical. There probably are niches for human workers on a moon base, but only until our robot technologies are somewhat more mature than they are today; Mission Control would be a lot happier with a pair of hands and a high-def camera that doesn't talk back and doesn't need to go to the toilet or take naps.

When we look at the rest of the solar system, the picture is even bleaker. Mars is ... well, the phrase "tourist resort" springs to mind, and is promptly filed in the same corner as "Gobi desert". As Bruce Sterling has puts it: "I'll believe in people settling Mars at about the same time I see people settling the Gobi Desert. The Gobi Desert is about a thousand times as hospitable as Mars and five hundred times cheaper and easier to reach. Nobody ever writes "Gobi Desert Opera" because, well, it's just kind of plonkingly obvious that there's no good reason to go there and live. It's ugly, it's inhospitable and there's no way to make it pay. Mars is just the same, really. We just romanticize it because it's so hard to reach." In other words, going there to explore is fine and dandy — our robots are all over it already. But as a desirable residential neighbourhood it has some shortcomings, starting with the slight lack of breathable air and the sub-Antarctic nighttime temperatures and the Mach 0.5 dust storms, and working down from there.

Actually, there probably is a good reason for sending human explorers to Mars. And that's the distance: at up to 30 minutes, the speed of light delay means that remote control of robots on the Martian surface is extremely tedious. Either we need autonomous roots that can be assigned tasks and carry them out without direct human supervision, or we need astronauts in orbit or on the ground to boss the robot work gangs around.

On the other hand, Mars is a good way further away than the moon, and has a deeper gravity well. All of which drive up the cost per kilogram delivered to the Martian surface. Maybe FedEx could cut it as low as $20,000 per kilogram, but I'm not holding my breath.

Let me repeat myself: we are not going there with rockets. At least, not the conventional kind — and while there may be a role for nuclear propulsion in deep space, in general there's a trade-off between instantaneous thrust and efficiency; the more efficient your motor, the lower the actual thrust it provides. Some technologies such as the variable specific impulse magnetoplasma rocket show a good degree of flexibility, but in general they're not suitable for getting us from Earth's surface into orbit — they're only useful for trucking things around from low earth orbit on out.

Again, as with interstellar colonization, there are other options. Space elevators, if we build them, will invalidate a lot of what I just said. Some analyses of the energy costs of space elevators suggest that a marginal cost of $350/kilogram to geosynchronous orbit should be achievable without waving any magic wands (other than the enormous practical materials and structural engineering problems of building the thing in the first place). So we probably can look forward to zero-gee vacations in orbit, at a price. And space elevators are attractive because they're a scalable technology; you can use one to haul into space the material to build more. So, long term, space elevators may give us not-unreasonably priced access to space, including jaunts to the lunar surface for a price equivalent to less than $100,000 in today's money. At which point, settlement would begin to look economically feasible, except ...

We're human beings. We evolved to flourish in a very specific environment that covers perhaps 10% of our home planet's surface area. (Earth is 70% ocean, and while we can survive, with assistance, in extremely inhospitable terrain, be it arctic or desert or mountain, we aren't well-adapted to thriving there.) Space itself is a very poor environment for humans to live in. A simple pressure failure can kill a spaceship crew in minutes. And that's not the only threat. Cosmic radiation poses a serious risk to long duration interplanetary missions, and unlike solar radiation and radiation from coronal mass ejections the energies of the particles responsible make shielding astronauts extremely difficult. And finally, there's the travel time. Two and a half years to Jupiter system; six months to Mars.

Now, these problems are subject to a variety of approaches — including medical ones: does it matter if cosmic radiation causes long-term cumulative radiation exposure leading to cancers if we have advanced side-effect-free cancer treatments? Better still, if hydrogen sulphide-induced hibernation turns out to be a practical technique in human beings, we may be able to sleep through the trip. But even so, when you get down to it, there's not really any economically viable activity on the horizon for people to engage in that would require them to settle on a planet or asteroid and live there for the rest of their lives. In general, when we need to extract resources from a hostile environment we tend to build infrastructure to exploit them (such as oil platforms) but we don't exactly scurry to move our families there. Rather, crews go out to work a long shift, then return home to take their leave. After all, there's no there there — just a howling wilderness of north Atlantic gales and frigid water that will kill you within five minutes of exposure. And that, I submit, is the closest metaphor we'll find for interplanetary colonization. Most of the heavy lifting more than a million kilometres from Earth will be done by robots, overseen by human supervisors who will be itching to get home and spend their hardship pay. And closer to home, the commercialization of space will be incremental and slow, driven by our increasing dependence on near-earth space for communications, positioning, weather forecasting, and (still in its embryonic stages) tourism. But the domed city on Mars is going to have to wait for a magic wand or two to do something about the climate, or reinvent a kind of human being who can thrive in an airless, inhospitable environment.

Colonize the Gobi desert, colonise the North Atlantic in winter — then get back to me about the rest of the solar system!



Charlie, I essentially agree with you on all of your points, though I'm not sure that will prevent us from colonizing.

Leaving aside ideological arguments -- only 3 of the original 13 colonies were founded for ideological reasons, and they got their funding because investors were stupid. Despite what our national mythos might have us think...

And barring FTL -- which is the only way we'll get the traditional interstellar colonialism of SciFi and Space Opera.

The only way I see interstellar colonization happening is via seedships. Leave out the human you postulated in your trips, just send self replicating machines with instructions on how to recreate earth life and humans to target stars. They can take a couple centuries, however long your machines last, it doesn't matter. Even then, I think antimatter would be the only power source that's reliable, unless you could count on Earth to beam power to a ship for a century or two -- not something I'd place my faith in.

So you'd load up your ship with enough energy to crack open a planet's crust and send it out, never to hear from it again unless you happen to be immortal. Once there, the ship would get to work, mining the target solar system, doing terraforming as needed, building industry and settlements, and only then creating the colonists. Perhaps we'll have tech to digitize human minds, in that case we might have some actual people from earth to resurect into new bodies. Otherwise robots are raising them from scratch.

Of course, the catch here is that to do this we need a post-scarcity economy and AI of some form or another. Which means that we could be doing a lot more interesting things back in the Solar System.

If interstellar colonization does happen, it will be as an afterthought of some eccentric post-humans.

As for colonization in the solar system, we'd need to discover some economic rationale that's not there right now for it to happen. We could make colonies on the Moon or Mars within the next century, if there was something to justify the cost. Giant self contained cavern cities if nothing else. Or we might be able to terraform Mars over the course of a few centuries. That would make colonization much more practical, even if there's no Earth-Mars joint economy, some people would settle on a terraformed Mars. Of course, that raises the question of who would terraform Mars which brings us pack to post-humans with time on their hands...


The assumption of decelerating at the destination is a killer. It squares the mass ratio. Hence one thinks of (1) what can usefully be done at the destination if there is no deceleration of the entire payload; and (2) can one decelerate without rocketry?

Two useful links:

Starflight without Warp Drive


Hydrogen Ice Spacecraft for Robotic Interstellar Flight


Typo: "Mars is a good way further away than Mars". ITYM "than the Moon".

Good piece - pretty much in line with what I've been thinking, though you've actually done the 1st-order approximation of the math.

The only reasons I see for putting humans on Mars, at least until we have a major technology breakthrough, are PR and politics. I'd rather spend my money elsewhere.


But, But, you miss the essential purpose of interstellar travel. Obviously, it's to find new life forms, hover in front of rural individuals, occasionally abducting them and probing their nether orifices. Of course this might be achieved by robotic probes but that would take all the fun out of it.


Andrew G: are you including the failed colonies in that count? Not just Roanoake, but things like the Darien scheme?

Hildo: typo fixed, thanks.

Personally I'd rather see the money spent on manned Mars expeditions than on aircraft carriers and nuclear weapons. The weapons will either soak up huge amounts of cash and do nothing, or they'll maim and kill huge numbers of people for no reason that will make sense even fifty years later[*]; whereas the first Mars expedition, however over-budget and uneconomical, will be one of the landmarks of history. (Yes, I do have a romantic streak, however tightly I try to keep it reined in.) Unfortunately I fear it's not an either/or choice between weapons and space at this point in time.

[*] I will concede that it is possible to make a case for some wars being morally justified, but I don't see any on the horizon as remotely unequivocal as, say, the struggle against Fascism in the 1930s and 1940s. And certainly not enough to justify the delta from peak cold war US military spending to current US military spending — which, even if you set aside the ongoing costs of the Iraq occupation, is about equal to a gold-plated crewed Mars exploration program every 18-24 months.


typo: setting the Gobi Desert -> settling the Gobi Desert?


Stephen, that's Bruce's typo. But I'll fix it anyway ... :)



I enjoyed reading the essay. The metaphor alone puts so much into perspective. Maybe my optimism got the better of me when starting the thread over at Asimov's, but it still made for some fun speculation.


Charlie: If you count all the colonies, rather than just the ones that were around in 1776, there were far more both economically and ideologically motivated ones. For instance, Puritans also settled in the Bahamas in an attempt to do what they did in New England. And Plymouth Colony destroyed the colony of Merrymount, basically because the founder was trying to set up a society the opposite of their own. There's a big list...

I completely agree with you about military vs. space spending. I'd far rather see a moonbase or mission to Mars than a war and bloated military. Even half of the world's military budgets could do amazing things in space. And space programs could support the same industries and create jobs like the military does. Research spin-offs would be even more beneficial to the economy if anything. Just imagine the uses the technology put into autonomous robotic exploration of Mars would have on industry here on Earth. Exploiting and colonizing the Arctic and Antarctic would be childsplay compared to Mars...


I think expansion into interplanetary space is much more plausible than colonization of solar planets; the easy availability of energy might be an economic enabler. The North Sea, I think, is a red herring--space habitats will necessarily have controlled environments. There are major, and difficult engineering problems, mostly to do with life support, and these aren't resolved yet, but, granted a space elevator technology, it's a fairly plausible thing to do, and there will be people who want to go. This also touches on the reason that space is different from earth's oceans; earth's oceans are full of life. But perhaps, eventually, interplanetary space will also be full of life. As for interstellar travel, I wouldn't rule out a magic wand; we've already discovered many magic wands; the physical world seems to have back doors. On the other hand, we don't have that wand yet, and you're right--it's not going to be done until we have it.

"We live in extremely interesting ancient times."


I've always thought the same about the distances, and when seen it put in Earthly perspective-terms really shows it. That's why I don't believe in UFO's or even SETI at this point. The distances are daunting!

  • most folks have no idea of this, in fact, most layfolk see little difference between stars and planets, at least in their daily lives, and think we know all there is to know!

Randolph, I figure space colonies are technically feasible -- subject to issues like how to avoid being slowly fried by high energy cosmic radiation -- but there are other social problems. Imagine you get the offer of a chance to emigrate to a frontier city. (Yes, it's going to be an intensely urban environment, even if there are arms and parks there. Urban equals high volume to surface area ratio, and the surface is where you intersect with the hostile environment, so you want to keep it as small as possible compared to the habitable volume.) The problem is, your ticket is going to cost you $25,000. (Going by the more optimistic cost estimates for getting into orbit via a space elevator, plus some subsequent rocket travel.) Do you take it? Well, when moving to a new city, one of the first things you ask is, "what are the neighbours like?" Now imagine that you don't know the answer to that question for sure (because the city is as far away as Antarctica) and the cost of a round trip to see if you like it is $50,000. What do you do?

Small introverted city-states could go anywhere. They could turn out to be as laid back and civilized as Amsterdam, as uptight and draconian as Singapore, or as dangerous and violent as Mogadishu. And unlike on Earth, you can't walk away. Walking out and becoming a refugee is not an option if things turn to shit. You're potentially in a backs-to-the-wall situation.

Circumstances, social expectations, and communications bandwidth may moderate this picture, but it's altogether too much like throwing yourself on a raft in the middle of the Pacific for a five year voyage with a bunch of strangers for my liking.


Charlie, well, yes, but you're not 20 any more--younger people have fewer ties and are more willing to break the ties they have. There will after all be reporting and correspondence from space cities, as well as trade--they won't be complete unknowns. Broadly, I think the pattern will be similar to the conquest of North America; first small groups, then expansion and, if travel becomes cheap enough, actual migration. At least it will not be actual conquest; as far as we know there are no natives to object (unless interplanetary space is full of energy creatures). I can easily imagine the second wave of immigrants being refugees--that was after all the big drive behind post-1850 immigration to the USA, as indeed it is the drive behind Mexican immigration to the USA at this time.


In Phoenix and Vegas we have colonized the desert.

The reason that Mars or the Moon might make sense is the same reason that these artificial cities are growing by leaps and bounds to this day. That's politics. Why today do people flee perfectly good hometowns with much more livable environments in Massachusetts or Illinois to move to Phoenix? Why did thousands of Mormons journey to Salt Lake? For the same reasons, others will someday flock to the moon.

The distance from meaningful political control, like America's 1800's distance from control will be the draw. Maybe they are pirates or a religion or prisoners or eugenics freaks, but $10 million/family will seem cheap to them. Also expect that we would not like it at all. Imagine the anger at Osama sitting up there in the moon broadcasting taunts, untouchable by anyone.

If the world could credibly agree not to ever interfere at all with the North Atlantic or Gobi the same inrush would happen there.


Josh, I hear where you're coming from and raise you Jonestown.

On the plus side, if we see "Osama sitting up there in the moon broadcasting taunts, untouchable by anyone", then he and his followers can't touch us. We get to regain some of the sense of space we've lost from our home world over the past two centuries. (Back then, a month's wages and 48 hours would get you across the English home counties, or maybe Massachusetts, by stage coach. Today it'll get you to New Zealand and back, the long way round.)

It'd suck to be a woman or an apostate in such a society, though. (Especially when they put you in the airlock without a spacesuit for getting uppity ...)


Boing Boing summarizes your essay as explaining the futility of space exploration, but as even you explained at the start of the article state, its only futile on economic grounds, but ideological grounds know few boundaries of wallet or logic.

The argument of not putting all out eggs in one basket is pretty powerful, and one that could easily motivate a multi-billionaire philanthropist to spends a few billion on a seed ship. Its notable that many of the backers of commercial space expansion are our internet age billionaires with nothing better to do with their money.

Yes, space colonization is futile from a mass emigration point of view, but it seems inevitable that 50-100 years from now humanity's seeds will be spreading far and wide.

We do still throw out messages in a bottle into the ocean, dont we?


Surur, you interest me: would you like to explain why "the argument of not putting all our eggs in one basket" is so powerful? That is, what can it do for you, for me, or for anyone else on this planet today?

(Hint: I think it boils down to a category error we often make, in confusing our own self-interest in not experiencing personal extinction with the existence of a species-wide collective self-interest in not experiencing species extinction. But I'd be interested in hearing other explanations.)


I say anybody so intimidated by the stars shouldn't write science fiction anymore.


It may be in part a category error, but it also could be a biological drive that says "continuation of the species is important to me", the same one that helps people decide to have children. From an economic standpoint, having kids is not a wise decision. You diminish your earning power, add another ongoing cost sink to your household, and any economic return you might see at the end of the day is limited and possibly nil. And yet people decide to have kids all the time.


Your argument does make sense, but so did the arguments at the turn of the 20th century that we would never reach the moon. It simply was not economical to build the giant cannon required to blast monkeys into orbit. So, yes, with today's technology, interstellar travel and interplanetary colonization remain more viable plot devices than possible human futures.

One other thought, interplanetary colonization represents a strong selection pressure for those humans who have the psychological fortitude (or psychosis) to want to be ripped from out little blue jewel here and plopped onto a barren wasteland. Maybe the universe favors extremists? History does have precedent here, e.g. Mormons/Utah, Calvinists/North America, Scientists/Antarctica. I'm just saying.


Von Braun was pessimistic about interstellar travel too! We should try fixing the mess on Earth and renewably survive and detox for a few generations before shipping our problems to space. The Apollo missions and a possible manned expedition to Mars have and will give us the perspective and hope to be able to sustain this work.


Grant @18 ... I'm currently writing a space opera. One that plays by the scale-factor rules. (It's not impossible, it's just rather an interesting challenge.)

If I'm going to try and write hard-SF, I'd rather get it right than risk tripping into a puddle of vacuous misconceptions and mistaking it for a universe of possibilities.

Stephen @19: I'm deeply suspicious of appeals to biological drives, because as a species we seem to exhibit rather a remarkable degree of behavioural plasticity. I know Richard Dawkins has taken to stomping on lots of peoples' bunions recently, but I would still strongly recommend reading "The Extended Phenotype" to anyone who still believes in group selection arguments. As for teleologists and believers in some numinous destiny, that's basically a religious argument and not falsifiable (or worthy of airtime, IMO).

As for lots of people deciding to have kids ... I assume you don't live in a country where the total fertility level is sub-replacement, right?


Perhaps I'm reading the article wrong - but you seem to be saying space travel is just plain futile. Not only for now, but for all time.

Although you do a good job "scaling" the journey of space travel, you don't do anything to scale the advances in travel that mankind has made.

A few hundred years ago, travel from NY to LA took months, now it takes hours. It's proposed that in the near future, that trip could take minutes (i.e scramjets). You talk about the journey to reach Jupiter taking years, yet the New Horizon's probe just did it in months.

I'd put my money on the fact that Technology will move us closer to choice C (i.e. the "magic wand" method) then most people can probably imagine. It might not happen in my lifetime, but I'm betting that the technology that got us from "first flight" to "space flight" in less then a hundred years has a few surprises left for the future of mankind.


Lance @20, I thought I was being fairly clear: I've got a beef with magical fantasies about space colonization -- not the same thing as space exploration -- and I'm interested in extrapolations that play by the rules and eschew magic wands and silver bullet solutions for dealing with the physics werewolf. Obviously the prospects for a lunar expedition didn't look good at the turn of the 20th century, unless you were Konstantin Tsiolkovsky, and even then, it wasn't until somewhat later that folks like Herman Oberth and Robert Goddard began trying to actually build liquid-fueled, and later multi-stage, rockets.

You'll note that I explicitly mentioned starwisp-type probes, nanotechnology, and uploading as possibilities -- then decided not to explore them. Because, y'know, we don't have any definite knowledge of whether they're even possible, yet. If they are possible, then we may actually be able to contemplate interstellar colonization at a not-too-outrageous price -- and we may even be able to go and visit the neighbours -- but it's going to look very different from your traditional SFnal scenario.

VonSkippy @23, see this earlier blog entry. Note also that the energy input required to attain a given non-relativistic velocity scales as the square of the velocity, not linearly, and if you want to decelerate at the other end and are using a reaction drive it effectively scales as the fourth power of the velocity. For relativistic travel -- anything much above .4 of c -- it gets even worse.

(Do kids actually still study physics in school these days? I despair ...)


Charlie, I see your point. But sitting here with my kids running amok while I'm trying to focuse, I can't help myself. I do hope for a universe with a human presence! If I had a quadzillion bucks I'd invest them in human space colonization anytime... (AND it can be argued that everything we do is motivated by selfinterest, so why not this???).


Charlie @22: I don't think a biological drive is the whole story, or necessarily the majority of it. People choosing not to have children is a fine example of how we ignore any effect of such drives. However, having children or not having children is, assuming you're in a first-world country, a decision with personal ramifications and costs that you can quickly figure to first order. The costs of space travel aren't nearly that easily figured out by people. As proof, I'd point to the response to this very post.

And country of origin doesn't really enter in: there are still plenty of people across the globe deciding to have children, even if the probability of such declines with increasing education and purchasing power.


Doing deeds for all time is a real and proven motivator, and has the immediate benefit of glorifying the person who initiated the effort in the first instance. Without this motivation we would never have the Sistine Chapel for example.

The whole conservation movement is about inconveniencing ourselves now for the benefit of distant future generations. When we talk about limiting global warming in 2050, anyone in their 30's will probably dead by then.

Sure, "putting all our eggs in one basket" is less powerful in dictating our spending priorities than having a bigger screen to watch TV on, but Americans have been happily spending $55 per year on just that by funding NASA.

To bring this ramble to a close, the immediate benefit to the donor is the same as sponsoring a puppy/gorilla you will never see, for the civilization that launches such a probe it will bring a similar amount of glory as other massive ego-boo projects, and it satisfies our biological drive to perpetuate our DNA, even if its only distantly related.

There seem reason enough for us to launch at least a few every hundred years, and it only takes one to succeed for us to have a interstellar civilization in 1000 years time.


Mrf, I forgot one other point, so a back-to-back post. Charlie, have you had a look at the newer multilevel selection theories? I know Dawkins isn't persuaded by them, but there are some aspects of e.g. Wilson's work that I find intriguing.


Surur: okay, I see where you're coming from. (And if there was an international equivalent of NASA you could subscribe to, I'd be in with my $55 a year on general principles.) But I still maintain that the urge to immortality thing -- at least when divorced from reproduction -- is essentially religious in tone; you won't ever see any results, so you're basically doing it on the basis of faith in something you will almost certainly never see.

Interstellar civilizations (as opposed to interstellar colonies) strike me as being an absurd idea, but that's another essay. Put it this way: in the absence of cheap FTL travel or other "magical" solutions to the scale problem, what on earth is there to bind two interstellar polities together -- except possibly the exchange of cultural data, bartered on a tit-for-tat basis ("I'll keep exporting my soap operas as long as you keep me updated on yours")?

Stephen @28: Nope, I'm woefully out of date in evolutionary biology.


And how!

It's weird how it's always the libertarians and conservatives who are into this crap. They think it's bad for society to care for the sick, or to protect the environment of the only habitable planet we've got, but wet themselves dreaming of The Human Species colonizing other planets, even though as explained above it's economically pointless and well-nigh impossible. That includes you, Jeff Bezos.

Just for fun:


Title: A bill to establish a National space and aeronautics policy, and for other purposes.

"Title IV: Government of Space Territories - Sets forth provisions for the government of space territories, including constitutional protections, the right to self- government, and admission to statehood."


"unless interplanetary space is full of energy creatures"

Well, there's our endless energy supply right there! That's whyu we should go into space - to capture and enslave these energy creatures.


Charlie @12 typo "arms and parks": ITYM "farms and parks".


Executive decision (this means you, Cole :) ... I am willing to fix typos in the original essay, but life's too short to fix typos in comments!


Charlie, your reasoning of dismissing not putting our eggs in one basket of "That is, what can it do for you, for me, or for anyone else on this planet today?" is incredibly myopic. By your reasoning, we should abandon any efforts into reducing pollution, global warming, etc. since anything we do today can't harm us in 50 years, no matter what it does to our children's children.

While I agree that colonization may not be practical from the economic standpoint, simply saying that it doesn't benefit you today is a selfish reason.


As we know (mostly to the detriment of the world) religious ideas are very powerful motivators.

Regarding the trade in ideas, we are half-way there already. With automated fabrication they will only become more so. In the end, it will come down to energy, matter and ideas, and two of those are commodities.

With individual wealth and power increasing, some billionaires will chose to make atom bombs, and some will fund star wisps. Its inevitable. They may even stock it with their own embryos.


"can't even figure out how to live in the Gobi desert or the ocean's floor" ???

We're not even really trying, so I wouldn't say "can't" - can't be bothered, perhaps.


Interesting article. I agree that deep space exploration will have very little effect on the lives of people for a few generations to come but human beings are very inventive and are bound to discover methods of travel we can't even conceive of. We're nomads, we always want to see what's over the next hill. I say 'we' when I mean 'them'; you and I will be long dead but our species will be out there colonising the universe; perhaps that's how we got 'here' in the first place....


typo: are robots are all over it already. Ours are, indeed.


Typo: "are robots are all over it already" (are = our).

As a species, we do things which are altruistic, benefitting an unrelated group. We pay taxes, which in some countries are part used to fund educational services which tax payers without children do not benefit from. Police officers intervene to protect strangers and firemen rescue people from burning buildings. Soldiers voluntarily fight for their country, an abstract concept if ever there was one. Other complete strangers have been known to put themselves at risk to save a drowning child who is not their own. We assume that these acts are part of civilization and society, and when they are not the dominant tendencies, we say that civilization has broken down, or society has failed. As a species, we're also very hung up on moral codes, which is no accident, but is the thing that makes civilizations and societies cohere and function. The confusing thing is that there obviously is an evolutionary basis for both group level altruism and imposition of moral structure, but I am suspicious about appeals to group selection. Anyway, maybe it's a combination of altruism and an attempt to attach it to a moral framework that leads to the "all-our-eggs-in-one-basket" justification for space colonisation?


Charlie, Kim Stanley Robinson's Mars trilogy is one of my favorite depictions of solar system colonization. The idea of wiping the slate clean and struggling to build a utopian government from scratch appealed to me, and I also liked the way Robinson portrayed colonization as a mechanism for the various cultures and factions of Earth to find their own space. Just as a reader with no scientific background, I found it plausible. But, Charlie, would you say that Robinson's scenario, which involves space elevators and terraforming, falls under the category of a magical fantasy about space colonization?
I do have an insatiable hunger for reading space opera, and I was pleased to see in No. 22 that you are writing something in that subgenre, despite your skepticism about the real-world possibilities of colonization. I'll be interested in seeing how you handle the scale-factor rules. I stumbled here via Andreessen's list of the top 10 sf authors of the 00's, and based on the descriptions there, I'll pick up "Singularity Sky" and "Iron Sunrise" as entry points into your work.


cjp, I think the Mars trilogy is about the most totally optimistic take on solar system colonization that I can absorb. Even so, he rushes it -- giving his protagonists longevity treatments so that they can see out a 300 year project, and then pushing through the terraforming of Mars in a fraction of the sort of time period currently considered necessary.

(The current space opera project I'm working on sidesteps the problems of human space colonization by, er, sidestepping humanity 1.0. We are, after all, the weakest link in the whole endeavor. So I suppose you could reasonably accuse me of waving a magic wand. My excuse is that it's a work of fiction, and I'm not using a really big wand :)


As a slight correction, it takes only two and a half years to get to Jupiter using a Hohmann orbit.

I have other comments on Economist's view web log.


John: I was looking at a table of round trip times, not one-way. Fixed.

The species survival utility you mention is an interesting one, but as I've noted, it's not a clear economic benefit to us, here on Earth, to know that humans on another planet or space colony will survive even if we're clobbered by a wandering comet. If that's a concern, it makes a lot more sense to put the money into detecting and developing techniques for zapping Earth-grazing comets, or remediating environmental problems here on Earth, than it does to try and bootstrap a colony in a hostile environment while writing off 99.99999% of the existing human species as colateral damage.


As for magic wands, modern cosmology probably has at least three up its sleeve: dark matter, dark energy, and whatever it was that drove inflation in the first 10-33 seconds of the big bang. There are a half dozen more gaps in the foundations of physics that don't get as much attention as unifying the standard model of quantum field theory with gravity right now. Dark energy is specifically an anti-gravity phenomenon.

But these are all red herrings if we don't care to exploit them. So we need to understand why we care. "Darwin's universal solvent" undergoes a mind-bending amplification when evolutionary variation finally discovers modes of organization that are capable of imagination and planning. Species whose individuals envision their descendants' survival and work according to plans for that survival have survival rates higher than species of equal complexity whose individuals don't care.

Ever since earlier primates discovered their ability to plan for their childrens' futures, we've been selected for caring about our kids' future and doing everything we can to make sure that they have one.

Even if group selection doesn't work for ants or fishes, it is surely working for H.sapiens now.



But. Even with todays technologies, we could have viable orbital habitats. Oh, not the tin-can ISS, but places where we actually look into 0-G chemical and biological synthesis. And we only have to haul most of the raw materials UP, the transfer vessels downwards don't have to be a spaceship, they just have to fall correctly.

Oh, and an asteroid capture mission is viable as well. Even NASA is considering looking at a near-Earth orbit asteroid visit. That could be interesting.


George @44: yup, you're not wrong. I'm going to be curmudgeonly and insist on standing on my base until some sort of application of one of those wildcards in physics comes along -- see also starwisps, mind uploading, etcetera -- but I'll admit the possibility. Your point wrt. group selection is also worth noting. (I'd like to add, though, that sometimes human beings do things that are really fscking stupid, maybe with a side order of evil on top -- under the fond illusion that they're doing it for ends that justify the means. We may be trying to do the right thing, but it does not follow that the thing we are trying to do is right.)

Andrew: I'd love to see even a one-person closed-cycle biosphere run for twelve months on end. We're crap at that kind of environmental engineering. Nuclear subs that can cruise underwater for months nevertheless are able to exchange gases with their ambient fluid (and extract oxygen by electrolysis); the Space Shuttle is so leaky it gets through a complete air change in about a week, IIRC. Humans only consume a few kilograms of oxygen per day, so for short to medium duration space missions -- anything up to a 300 day sojourn on a space station -- it makes sense to ship LOX and food along, rather than to grow/recycle your own. Which means we've never really had to take that kind of recycling seriously before. But the first remotely serious attempt at space colonization will have to do so ...


I'm surprised no one has mentioned Robert Zubrin's The Case for Mars. Zubrin makes a very thorough case for the idea that Mars settlement is not merely feasible, but fairly straightforward, using existing technology. He also does some math I don't pretend to understand saying that it's actually less fuel-intensive to settle Mars than the Moon.


Solid article. Well researched. The math seems optimistic. Real-world cases probably come out significantly worse than you estimate.

Robert L. Park has a chapter debunking manned interplanetary space flight in his 2001 book Voodoo Science.

As for space colonies...the International Space Station, as everyone just heard, nearly shut down due to a computer glitch. 100 billion to support 3 people in orbit, and it almost became uninhabitable 'cause of a computer crash. (Doesn't make you too optimistic about uploading your consciousness, does it? AN UNEXPECTED APPLICATION ERROR HAS OCCURRED - CORE DUMP OF YOUR CONSCIOUSNESS BEGINNING...) So much for L5 colonies or Solar Power Satellites.

The real problem with manned interplanetary space flight, as Park points out, involves human exposure to cosmic rays. Estimates suggest that an unshielded crew would get enough high-energy nuclei blasting through their bodies to die from cancer during a trip to Mars. Hohmann transfer orbits obviously greatly worsen this problem, since they take the longest time. TANSTAAFL.

As an example of just how high energy these cosmic rays are, Apollo astronauts reported seeing intermittant flashes when the particles blasted through the vitreous humor inside their eyes. There's also the issue of osteoporosis caused by microgravity. Exercise doesn't seem to help much.

Enough shielding to cut down the cosmic rays to a survivable level would increase the payload so much that the rocket equation beats you to death. Of course, a magnetic shield offers an alternative possibility, but once again, at a brutal energy cost. TANSTAAFL again.

The thinking now is that space elevators might not be practical since they'd take passengers through the Van Allen Belt -- lethal radiation again. Once again, shielding issues, a huge increase in the cost per pound to orbit: once more, no free lunch.

Alas, you'd need a truly huge rotating wheel to generate artificial gravity and avoid osteoporosis. A smaller rotating capsule risks Coriolis effects which could give you a ceberal embolism if you turned your head too fast. Once again, a great honking Battlestar-Galactica-type spaceship is required to support a huge rotating wheel for artificial gravity. Of course, we might be able to fix the osteoporosis problem with gene therapy. Not so sure about the cosmic ray issue. Maybe. Gene therapy might be a free lunch there. Peter Watt's novel Blindsight uses that technique during the protagonist's trip back to earth.

Ah, for the days of Niven's World of the Ptavvs, when fusion-powered torchships accelerating to Neptune at one G seemed plausible...


Hmmm.... you also don't take into account that lifespans are increasing quickly. Would a person who takes LiveForever(TM) medications and a ton of medical DNA-resequencing equipment with an extended lifespan of 5 or 6 centuries even care about a 50-year space voyage??

And don't be so negative about propulsion technology.... we have gone from 35mph to Mach20 in the space of only one century. Would not a stone-age villager in Borneo (they still exist) looking up at the contrail of a 747 or SR-71 wave it off as "magic technology"??

I am heartbroken that we stopped the Moon flights 30 years ago and wasted our time with the Shuttle, but the only thing we'll achieve by turning our backs on space is to doom mankind from either boredom or a stupid local accident.


Dear Charles: 1) Of course interplanetary and interstellar colonization are not going to look like the European colonization efforts. Nor did the European colonization effort look like the Indo-European migration that established those populations. Nor did the migration, 10,000 years ago, that established the Indo-Europeans; or the migration 100,000 years ago that established a human presence outside Africa. Different technology levels and different circumstances dictate different behaviors.

Barring the sort of magic wand you have used in your space operas, colonization of other bodies in this system will take decades or centuries, and interstellar exploration will likely be centuries to millenia even for the nearest stars -- at tech levels quite different from our current status.

This does not intimidate me. We are five centuries into the colonization of the Americas at this point, and approximately one hundred centuries into the out-of-Africa project. Are those doing well so far? Providing good returns on investment? I thought so.

2) Your estimates on launch of humans from Earth assume all life support and other mass is to be launched from Earth. It has been recognized for upwards of fifteen years now that space travel cannot be large-scale economical without utilizing off-Earth resources. This requires extra start-up capital, which is why it has been delayed, but pays off in the long run.

I hate to break it to you, but your objections are not new and have already had some serious thought devoted to them.

3) You wrote: "But the domed city on Mars is going to have to wait for a magic wand or two to do something about the climate." Of course, that's exactly what terraforming is all about. I admit that I think terraforming would take more time than is posited in, say, K. S. Robinson's space opera; but that is mainly because I do not foresee much a massive capital investment in terraforming Mars. Your previous comments indicate similar sentiments.

Nevertheless, in the short run, I agree with you: I think the rest of the first century of spacefaring will be dominated by tourism, research, development, and manufacturing in Earth orbit, one or more bases on the Moon (some research, some tourist), probably one research base on Mars, and perhaps some mining bases in the asteroids to deal with the automated mining fleets. That's what we are capable of with current-plus-immediately-researchable technology.

I also think technology will not sit still, and I know you think the same. It won't stay that way. Take Robinson's story again: asteroid colonization doesn't take place until the 23rd century, after a century plus of deep-space mining operations advance the technology far enough.

4) You wrote: "Colonize the Gobi desert, colonise the North Atlantic in winter... then get back to me about the rest of the solar system!"

Be careful for what you ask for; you just might get it. The point about Las Vegas has already been made, of course. The Inuit are another counterexample, as are the Polynesians. In general, humans have proven to be remarkably adaptable to conditions.

However, your point is also specious because of the extreme proximity of the Gobi and the North Atlantic to more hospitable regions. If you want to live off the proceeds of the North Atlantic, you don't build a ship to sit in the North Atlantic; you live on Nantucket and Nova Scotia. You could alter the environment, but because the Earth's climates are interdependent we're not likely to do that. I do not foresee the Moon ever being colonized extensively; there's no point when Earth is so close.

The advantage of extraterrestrial environments is that, since there's no pre-existing life (except perhaps on Mars) to disturb, you can do anything you want to the environment. You can make it as pleasant as Earth is, for a suitable price -- all you really need is cheap energy (solar or fusion) and time. This is a task harder than European colonization of the Americas (where all the groundwork was done by the native Americans) but easier than the out-of-Africa migration (where the environment could not be altered, and had to be learned through trial and error with close to zero technology).

I read with amusement your description of Septagon system in Iron Sunrise. In lieu of Niven's Law of Fictional Assumption ("There is a technical term for anyone who thinks that a fictional character's biases and prejudices are those of the author's; that technical term is: 'idiot'."), I will not assume that you share the Eschaton's opinion of the space colonization crowd... but your essay does little to convince me otherwise. I agree with the implicit criticism that ideology will not conquer space. I disagree with the assertion that it won't happen. I agree with the assertion that it won't happen the way we expect. (Who predicted tourism and the dot-com boom as the keys to renewed rocket research? I don't think anyone thought of that...)

5) @14: I see your Jonestown and raise you Moses in Sinai. Now there was a crazy migration project if I ever heard of one... religiously motivated, too... probably wasn't pleasant to take part in... and yet look at all the civilizations whose heritage traces back to that one. Was it worth it?

6) @16: It is a personal choice as to whether you give a damn what happens after you die, if you have children, and whether you care what their survival chances are. If your answer to all these questions is "no" then few arguments (genetic, memetic, religious, or otherwise) will have much effect on your positions on long-term plans, as you have denied any possible benefit for making them. However, consider these corollaries:

a) Would you like to live in a world where the vast majority held the same position? b) Would you even exist if, in the past, the vast majority held the same position? If so, what would your life be like?

7) @46: I agree that closed-loop recycling needs more work. Do you really think that work will not be done?


Ack, for shame, Charlie! Even at sub-replacement, you still can't say that "lots" of people don't decide to have children! How many millions do, even in, say, Italy?

Nice essay -- but going by the usual rule, I'd say this almost guarantees that there will indeed be some kind of interstellar colonization. But yeah, it probably won't consist of transporting canned meat. Talk about doing something for religious reasons!

52:'s the bottom line: as the Moon landings, humans will walk on Mars Just To Prove it's not worth it. it will be done several times (not in my lifetime) and then abandoned. Portugal/Spain got the credit for the New World. USA got the Moon. ? Mars.


Another typo, penultimate paragraph:

'and live their for the rest of'


As far as seedships building people on the other end, I liked Alastair Reynolds' take on it. The people of Yellowstone in his main series with Revelation Space and such are the second people to have colonized their planet in near lightspeed craft. The first were from America (loosely) and built by automated systems on the other side, no live cargo. Of course, being raised by robots or computerized systems turns out to have not given them the requisite amount of proper human contact. Their personalities had some rather nasty quirks which were propagated culturally (the kind that seem to involve people using axes or otherwise going like "The Shining") and within a couple of generations, they had wiped themselves out...


Though the Sun is larger than the Earth, it is also further away.

You left out the Heinlein ("Universe") solution.


I have a dumb question, Charlie, prompted by the fact that I am writing this from Carolina, an incredibly pleasant suburb of San Juan.

Doesn't most of your solar system argument boil down to the fact that Earth is the only real estate worth squat in the vicinity? Unless I'm missing something --- I agree that a desire to spend money on species-survival is essentially religious, but is also pretty widespread --- your argument would change if Mars were a bubbly blue sphere with places like Carolina on it. Right?


There is a quasi-religious argument, based on the Gaia hypothesis, which states the whole point of intelligence is to spread the biosphere to other (hopefully lifeless) planets. Being a believer in memes and an infinity of parasites (self-inserting sequences on plasmids, plasmids, cells, organisms,flea, bigger flea, human, societies, nations, civilizations, planets and life itself) this has always seemed elegant to me.


The article was worth the read but you really need work on your author's tone. It's really condescending.


The most glaring error I see is what appears to pass for "moral thinking" in Libertarian circles:

"The future extinction of the human species cannot affect you if you are already dead: strictly speaking, it should be of no personal concern."

As if moral behavior is strictly limited to individual concerns. The author gets centuries of moral thought bassakwards. Chris @ 30 gets it exactly right.

The author also seems to perpetuate a number of myths about third-world economies and population rates. See Hans Rosling's : Debunking third-world myths with the best stats you've ever seen.

You didn't mention another major obstacle to space travel, even travel within our solar system... gravity. Astronauts who spend a lot of time in low gravity environments come back much worse for wear. I don't know the current knowledge, but it seems to me that any prolonged trip, even if it is only as far as the Moon, is a one way trip. Your heart, weakened by having no resistance would not be able to handle the extra load of a return to Earth. Besides, what is the lifetime of a human on the Moon or Mars? We don't know. Our bodies are exquisitely tuned to 1g, how long will they even function in low or micro gravity? Many of our bodily systems depend on gravity to move our fluids around and remove waste products. All we are is bags of offal held together by thin membranes.

Peter Watts in Blindsight proposes an "antimatter-teleportation (telematter) drive". This is just for exploring within the solar system but has great promise.

As for an economic incentive, wouldn't the asteroid belt be a huge resource? Lots and lots of raw materials out there and in the rest of our solar system to boot.

I do agree with others who have said we should get our home on Earth in order first. If we don't get global climate change under control it is doubtful we'll make it past 2100 let alone survive long enough to fund interstellar exploration. Global warming 'is three times faster than worst predictions'


" your argument would change if Mars were a bubbly blue sphere with places like Carolina on it. Right?" But no Country Club. Or Hill Brothers.Or those public housing projects were they shoot at each other A la Gaza every few weeks. Right?


meh... so no monkeys get to jaunt around in space. sfw.

i think that's why i've enjoyed various authors takes on the robotic space travel/singularity premise, from clark to yours to vinge. we're too fragile to adapt to anything but terrestrial life.

but is that really such a great loss? what distinguishes us is that we're thinking monkeys. maybe all we need send is the thought, the meat can stay at home and enjoy a few more sunrises.

and thanks for the interesting comments. will have to steal some ideas for my own amateur writing....


...You know, between you and that idiot, Gregg Easterbrook, it's no wonder that the gullible are easily bamfoozled into thinking space exploration is a waste of time. If defeatist schmucks like you were in the right, Columbus - or anyone else - would have never set foot in the Americas. The fact that you and your ilk refuse to acknowledge is that it's in Humanity's basic nature to explore, to see what's on the other side of the hill. Your asinine argument demands that we, as a species, renounce what has clearly separated us from the beasts. If you're so adamant that this core aspect of human nature is a bad thing, then do us all a favor and remove yourself from having to deal with it directly.

Preferably before you contaminate the gene pool, natch.


Hello again. I just wanted to point out, Charlie's example of the Gobi Desert as a place we have yet to inhabit is only superficially true. It's true because there are no European cities there, but the place has been marginally inhabited for centuries, if not millenia, by nomadic tribes. The Mongols, for example, occupied that hellish place. Recently even, Chinese colonization, er "land reclamation effort" have created a modern city in that frigid sandbox. In fact it's called Shihezi looks pretty comfy to me.


I like the essay, and like that Cory et al point to it from BoingBoing, however they spun it.

The crude rule of thumb is that fission drives are 0.1% efficient at converting mass to energy, and fusion drives are 1% efficient at converting mass to energy.

Typing this from what was once The Old West, the economic bottom line is this. In 2007 dollars, a fully provisioned covered wagon plus horses, mules, or oxen cost in the $100,000 to $250,000 range

Families headed West, not for the land of milk and honey, but to get away from a family, employer, town, church, or government that they could not stand.

If the cost in 2007 dollars drops to the $100,000 to $250,000 range to put a family in Earth orbit, millions of people will go into orbit. If the cost in 2007 dollars drops to the $100,000 to $250,000 range to put a family on the Moon, millions of people will go to the Moon. Same range for Mars, millions go to Mars. Ditto asteroids.

A cubic kilometer of metal asteroid is worth a quadrillion dollars at current prices. After the first trillion dollars worth of nickel is brought to Earth (nickel foam lifting bodies down through the air, floated on ocean to port, melted to make stainless steel at a regular steel costs) the price of nickel will have equilibrated down to the price of iron, and something else must be mined. But much of that first trillion is profit.

The cost of transforming Mars from undeveloped real estate to fully developed real estate is also order of magnitude a quadrillion dollars. After that, it's all profit.

But my wife asks me to say the following

Re (5): Darien scheme.

Professor Christine M. Carmichael is well-along in writing an alternate history novel in which the Darien scheme succeeded. Mexico and Central America were developed by Protestant Scots. The USA has, in effect, two versions of Canada adjacent to it, one to the North, one to the South.


You make a stong case, but for a writer of science fiction, I would think that you would have a better imagination. Humans always seem to find ways around physical laws, or at least how to cheat them. Anything that we can think off now, we will have and far more. The electron microscope was only invented roughly 60 years ago and now we're building gears out of atoms for Christ-sake!


This is all a negative "can't do" article by a guy who writes about ninjas? He doesn't explore the possibilities of of close to C speeds or time dialation that could make the trip very short for explorers. He also agonizes over the required energy. without any mention of antimatter energy, solars sails or Bussard Ramjets, all of which have been speculated on for years and are becoming a reality.

Throughout history there have always been naysayers, but nobody will remember them.


for those of you raising an eyebrow at my reference to antimatter drive,,,

check this out...


Re: group selection. Yes, Dawkins has issues with it, but he's the reductionist to end all reductionism. If you pick your group realistically (e.g. semi-isolated human tribes) it can be shown to make sense -- particularly for beings such as us that rely so much on culture for our survival. Survival and the "inheritance" of traits then occur at the group level and off you go.

Which leads me to a related point -- who says any potential colonists would be strictly human? I don't mean human 2.0, but rather the results of cultural and biological divergence amongst human groups settling near(ish) Earth space on asteroids and so forth. If you're going to settle an inhospitable rock, it might as well be one with a really shallow gravity well. Throw in unregulated genetic fiddling and a few technological novelties, and you end up with groups who wouldn't see anything silly about life on a generation ship. Yes, I read Schismatrix when I was young and it warped my mind.


Re: 66:

(1) antimatter energy: like hydrogen-fueled cars, the concept is pitched to confuse energy generation with energy storage. By forseeable technology, making antimater in micrograms, let alone tons, is many orders of magnitude more expensive than other forseeable interstellar technologies. I knew Heinlein, who quoted me in his afterword to his Encyclopedia Brittanica article "P.A.M. Dirac, Antimatter, and You" in "Expanded Universe." We corresponded a bit.

(2) solar sails: "Project: Solar Sail" edited by Arthur C. Clarke, David Brin, and Jonathan Post. Penguin Books, 1990. ISBN: 0-451-45002-7 A collection of essays and short stories ...

(3) Bussard Ramjets, as we now understand them, in our part of the cosmos, are more like parachutes than engines; with drag greater than thrust.

I'm pretty sure that Mr. Stross knows the science and engineering of (1),(2),(3). These merely add footnotes to his essay. They do not undercut any of his arguments.

Of course there can be unforseen technologies. I'm sure that there will be. See, for instance:

"Space Travel in the Next Millennium", commissioned poem as summary/frontispiece of: Proceedings of Vision-21 (Space Travel in the Next Millennium, NASA Lewis Research Center, 2-4 April 1990, NASA Conference Publication 10059, 1991.

70: 66: The example drive that Charles uses for his example is WAY more efficient than any theoretical antimatter drive.

Antimatter isn't Propulsion Magic. It's an energy storage technique. The NASA article mentions that the ablative antimatter rocket has an Isp of 5,000 seconds. That's way more than what we can do now, but really pitiful for the task of fast interplanetary or interstellar travel.

Theoretical fusion drives can do a lot better; an Isp of 130,000 seconds was predicted for one type. (Inertial confinement fusion.)

That would make interplanetary travel fairly quick, but that's still not enough to make interstellar travel fast and easy.


Charlie said:

And unlike on Earth, you can't walk away. Walking out and becoming a refugee is not an option if things turn to shit. You're potentially in a backs-to-the-wall situation.

My sons would say, "So long as I've got broadband to my friends, who cares?"


It's not in my narrow self interest to have space travel but, as Richard Dawkins would point out, my genes have other plans. And after all, I'm just a robot my genes built to help them replicate.

If humans ever do go into space, which humans? I would like to suggest that the autistic are somewhat space pre-adapted. A reduced need for social bonds may reduce the necessary size of a generation ship.

If humans colonize the solar system, it will be those humans who then colonize other stars, so there'll be a double selection effect for that. The vanguard is going to build up momentum, and get stranger and stranger. Seems like a trip between stars would give you time to slow down and have some really big thoughts. No need to hurry.




Paul @72, that's an interesting idea there. A selection pressure that favors autism.


the case for space colonization isn't usually presented as an economic enterprise so much as a quasi-religious one

I wonder if this one sentence doesn't actually contain the undoing of the argument, at least in part. Restricting myself to the solar-system part for the moment, the argument against colonization is that it's economically silly, terribly unappealing and generally different & pointless. But surely religion is extremely good at getting people to do things like that? All one needs to see space colonization as a reasonable forecast is to take seriously the idea that the motives are quasi-religious, and imagine them developing into full-fledged religious ones (with or without any metaphysical trappings): if anything can get people to get into space despite economic problems, lack of surface appeal, etc, it's religious motivation.

Sure, the Gobi desert is under (un?) inhabited. But isn't Mecca in a desert? Millions of people go there every year...


Joel @71: I think your sons might feel differently if they lived in Mogadishu or even Baghdad. For the rest of their lives -- weeks, maybe. Charlie's point is that as long as there's a stable society, things are peachy. But human societies, especially in small, isolated communities, have a spotty track record. I take your point about broadband and isolation, and you're probably right that there's a mitigating factor. But Baghdad had and has broadband (of course, now it doesn't have much electricity) but it's still not way up on your list of places you want to live.

OM @ 62 - wow. Nice attitude, bub. I bet you win lots of popularity contests.

bill @ 66 - you, uh, haven't read anything Charlie has written, except this essay. Have you. Ahem.

Atom Ant @ 65 - same comment. Anybody who can come here and say Charlie doesn't have much imagination really needs to hie him hence to a bookstore or local library. I mean this. Or download Accelerando for a rainy weekend.

Noel @ 56 - Carolina is nice. But come down here to Ponce and you'll see why we say that "Ponce is Ponce, and everything else is parking." You know what town in Puerto Rico is closest to heaven? Juana Diaz (because it's closest to Ponce, get it? We got a million of'em.)

But yeah, I think Charlie's argument does boil down to the fact that Earth is the only real estate in the Solar System that comes with an oxygen and fresh water supply -- and that's a pretty damned good argument. If there were a Puerto Rico on Mars, beaches and all, well, then we would already have terraformed Mars and Charlie's argument would be moot.

Johnathon @ 64 - granted, a cubic kilometer of nickel is equivalent to a metric shitload of money, but why do you need canned meat to go out and get it? It's cheaper and easier to send the robots (OK, OK, after we can build them -- but as I take Charlie's argument, we can build robots much more easily than we can fire smart monkeys around the System.)

Paul @ 72 -- that's a real interesting idea there.


After all this, wouldn't it make the most sense to invest in SETI style communications - both receiving AND sending?

That way, if there is a way to effectively travel these distances we may find that out -- but if there has never proven a way to move about in the galaxy or at the interplanetary level, we may actually learn that as well. Essentially, it's currently the only form of intergalactic trade we know how to execute.

We could start with a simple sequenced laser pulse - like an interplanetary dial tone. Would that not be within both our technological and our financial capabilities?



You are correct on a lot of things, but you miss the forest for the trees.

As for anti-matter being an energy storage method - perhaps at some point in the future we will have an effective method to directly convert matter to anti-matter. Even if we don't, I still won't rule out interstellar exploration and colonization.

We have, frankly, more than a billion years to figure the problem out. Since you seem to like to use a condescending tone, I will return in kind: 1 billion years is at least 10000x the duration of human civilization. I'm pretty sure an idea or two will come out within that amount of time. As for the energy requirements - as we develop our technology, we will begin to take advantage of a greater and greater amount of the energy available - both from direct solar energy and from fusion and fission generation.

I also anticipate we will begin to improve our biologies and also develop cybernetic and robotic technologies to surpass many of our current limitations.

All your article really is simply a summary of how many challenges we will overcome in the eventually. An equivalent list could have been made for the moon landing (yes, the moon landing is vastly easier, but we have a LOT of time to work on interstellar colonization). I can wait a few thousand years. Well, not really (I'll be dead), but humanity can.


Actually, the North Sea oil rig comparison with O'Neil colonies occured to me when I was looking at a model of a futuristic floating city proposal. We don't build floating cities and we're unlikely to build space habitats to service solar power sats.

quasi-religious might also be a good term to the impetious behind the Apollo program. I sometimes wonder whether a milenia from now, people will regard them the way we regard the pyramids: an awsome engineering marvel considering the technology of the time. One that could be duplicated far easeir with current technology but nobody has any desire to do so and no gut understanding of the motivations that drove them to do it in the first place.

And of course high c fraction voyages as postulated in #62 just make the total energy/mass of an interstellar ship worse, not better.

Yes, matter/anti-matter is merely an energy storage system, but as the energy storage that could conceivably have the best energy/mass ratio that would probably be critical to any intersteller probe, robotic or human. Either is really only possible for a society that has Exawats to burn.


This earth is as much a paradise as it is a prison. We are bound to it so long as we remain shortsighted and ephemeral. Many of our present constraints are relative to the current human mind and body. However, our species is subject to great change.

Perhaps the time will come when millennia pass in our minds much in the same way as days now pass. Whether by technology or evolution, we will change as we make our way into the stars. Our bodies will adapt to the scale of the universe. Our emotions will reflect the impact of this change. It may not be unnatural for a future version of a "human," or a collection of "humans" to feel at peace with roving on some thousand-year voyage, contemplating the universe at an intellectual depth unfathomable by our present minds. In this frame of mind, our bodies may seem more fluid, changing shape like liquid as the years pass like milliseconds.

In other words, we will change to meet the constraints of our technologies.


"bill @ 66 - you, uh, haven't read anything Charlie has written, except this essay. Have you. Ahem" That's true, I got here via the boing boing post and it didn't register that this is charlie's site, so I apologize for the disrespect.

But I still think we willl develop interstellar travel by making use of anti-matter and time dilation. The cost or energy required isnt a problem because I figure we will be tapping into the sun's energy in a big way soon enough and then energy will be plentiful. Solar-powered-satellites...


Hi Charlie,

I enjoyed your essay quite a bit. However, I did have a few questions/comments.

First, you questioned the validity of arguments about "all your eggs in one basket" -- do you mean by this that you don't feel that humans are swayed by this argument, or that the argument itself is invalid?

It seems to me that the argument has a great deal of emotional power: it's fundamentally very similar to arguments about making the world better for our children, and so forth. So it seems to me that as an emotional argument, it's likely that people will continue to be moved by it. Will this be enough that people will expend great resources on the problem? I don't know.

I think that some other arguments can be made for space colonies in terms of Earth's self-interest, as well. For example, you can argue that it would be much easier to recover from a world-wide catastrophe if we had a widespread interplanetary presence, able to provide support and technological assistance. However, I'm not sure that sort of thing is really very credible.

For your point about closed societies in a small space colony, I wonder if some of the previous posters have it right: with modern communications technology, perhaps we're moving into an age where isolation is still compatible with participation in the greater society. For example, even in a small space colony of a few hundred people in say, a LaGrange orbit, would the internet/phones/news etc. tend to keep the colony in line? It might be hard to justify murdering your neighbor if you know the people you buy oxygen from will see it live on TV.

Of course, this argument is kind of opposite to one of the pro-colonization arguments I see above: will people move into space to get away from governments they don't like? If so... the moon may not be nearly far enough!

Also, it seemed to me that much of the argument about interstellar travel (which I agreed with) centered around (cheap) energy production. This made me wonder: many have posited that energy production is one of the great advantages to living in space, since sunlight is reliable and comparatively easy to manipulate there. Assuming an interplanetary civilization as a prerequisite to any interstellar effort, is energy production really that much of a problem?


Food would be an issue, though we could scoop up a ton of cheese off the moon and send that along behind the main spacecraft with a connecting sushi conveyor belt


Enjoyed the article.

There?s no question it?s a slim to none chance of us ever getting off this planet, let alone out of this solar system.

But???.. and there?s always a but??..there is no way to know what advances might occur in the future. What about a Blade Runner scenario? We create replicants to do all the tough colonization stuff, then join up with them later.

Whatever happens will be in phases. First a moon base, then a Mars base, then the difficulties of getting beyond the solar system will set in. But again who knows what technological or genetic advances will occur?

We do have a human presence in Antarctica, which is the closest thing we have to the Martian environment.

I think people know that colonization is a long shot, but man always seem to go where he is not meant to


I think the argument of not putting all our eggs in one basket is pretty bogus; fact of the matter is, we don't know how to design a self-sustaining ecosystem. Which means all those space colonies are going to be ecologically dependent on earth for the foreseeable future. "All true wealth is biological." In the end life, life that we can live with, is the most valuable thing in the universe to us, and the only place we know we can find it is on earth.

On reflection, James Blish addressed these issues in both Cities in Flight and The Seedling Stars--very specifically in A Life For The Stars. He definitely ransacked the magic wand shop for Cities, however. I can't recommend Seedling Stars, it has aged badly, but the last story, as a critique of racism, still has a great deal of bite.


Noel @56: you're damn right about my argument changing if that was the case. It'd still be difficult to envisage much in the way of trade, at least with current/forseeable technology, but a piece of real estate of that quality would be just within the budget and range of folks with a really pressing desire to leave the Old Country behind for good. (A large chunk of the problem I have with space colonization at current tech levels is that in terms of direct human experience there's no "there" there; just a succession of cramped metal rooms, some of which have windows with a view onto a place that will kill you stone dead in seconds if you ever break the glass. We need to either re-engineer ourselves to exist in such environments, or manage some really extreme breakthroughs, before they actually become useful places to us, as opposed to our machines.)

Alex @58: I prefer to think of my tone as "annoyed by idiots". Of whom there are many with an obsession on this topic.

Noen @59: I didn't comment on Chris's (@30) comment because, like you, I think he hit the nail square on the head. For some reason space colonization is a libertarian and conservative shibboleth, and their usual highly egocentric frame of reasoning gets inverted and/or thrown out the window completely when they get started on the subject of their pet hobby-horse. You should bear in mind that this essay is something of a debunking exercise aimed at this crowd, and when I started going on about the lack of personal benefits accruing from the "all our eggs in one basket" meme, that's the mind set I'm trying to confront with their own inconsistency.

NB: the asteroids turn out to be a lot further apart, energetically speaking, than we think. But as the current record for an astronaut cosmonaut staying in zero gee and returning to earth is Valery Polyakov with 438 consecutive days aboard Mir, we can put a lower bound of "more than a year" on the question of how long people can survive in microgravity. So that objection at least isn't insuperable.

Paul @72: that's a really good idea. (Excuse me while I make a note of it :)

Cober @78: As for anti-matter being an energy storage method - perhaps at some point in the future we will have an effective method to directly convert matter to anti-matter. That's an example of what I mean by a "magic wand". You're basically postulating a free lunch. "Why, if there was such a thing as a free lunch, I could dine out every day, for free!"

As for having a billion years to figure it out -- no, we don't. We, personally, have maybe fifty years, barring breakthroughs in medical research. Odds are that none of us participating in this thread are going to see much more than a renewed Lunar expedition, possibly a base there, and possibly a Mars mission, within our lifetimes. In the long term, the jury is still out on whether our form of tool-using intelligence is an evolutionarily fit adaptation; given that our species is probably less than 0.2My old and we've already triggered a once per 100My level major extinction event, I'm not sanguine about our long term prospects.

Justin @82: I judge the fund-raising effectiveness of the "eggs in one basket" argument by the efficiency with which it effortlessly raises tens of billions of dollars in funding for the project spaceguard project in the wake of the 1992 Comet Shoemaker-Levy 9 impact on Jupiter. (That was sarcasm in case you hadn't noticed ...)

On energy production: all we need to do is dismantle Jupiter, surround the sun with enough orbiting photovoltaic and thermovoltaic collectors to trap its entire output, and then use Saturn as a fuel dump, and of course we'll have plenty of fuel and energy for our personal fast relativistic starships. NB: there might be a few minor technical issues with implementing this program, but I'm game to start on it next Tuesday. How about you?


My original comment: As for anti-matter being an energy storage method - perhaps at some point in the future we will have an effective method to directly convert matter to anti-matter.

Your response: That's an example of what I mean by a "magic wand". You're basically postulating a free lunch. "Why, if there was such a thing as a free lunch, I could dine out every day, for free!" True, but you ignored "As we develop our technology, we will begin to take advantage of a greater and greater amount of the energy available - both from direct solar energy and from fusion and fission generation." There is a significant amount of potential energy available in fissionables & hydrogen in the solar system which are accessible to a civilization able to colonize the solar system.

As for having a billion years to figure it out -- no, we don't. We, personally, have maybe fifty years, barring breakthroughs in medical research. Odds are that none of us participating in this thread are going to see much more than a renewed Lunar expedition, possibly a base there, and possibly a Mars mission, within our lifetimes. It almost seems that you expect all human development to cease after you die.

In the long term, the jury is still out on whether our form of tool-using intelligence is an evolutionarily fit adaptation; given that our species is probably less than 0.2My old and we've already triggered a once per 100My level major extinction event, I'm not sanguine about our long term prospects. I agree that human survival is not guaranteed. But if we wind up having 1By, I would suspect that we will be able to crack the interstellar colonization nut. In fact, I would bet that 2000 years could do it, providing we continue to develop.


Unless the development of technology slows down, isn't it a little bit pretetious to think that there aren't any "magic bullets" out there to be discovered? I mean, if 100 years ago (1907) you said that man would walk on the moon 62 years after, you'd pretty much been declared crazy on the spot. Shouldn't we expect that the same is true about trying to predict 100 years ahead (or more) today?

The interesting thing is that development takes other paths than we think - I remember reading an article of future predictions written around 1968 - this had us living on the moon before 2000 and making the common cold extinct in 1990. But it made no mention of the computer revolution, for instance.

But overall, I agree that economics need to be considered - it is the favourable economics that has driven the electronics revolution (as well as making air travel available to anybody in the industrialized world).


You are a fine writer, if not a tad bit too condescending at times (this flirts with the "my Linux server is more secure than your Linux server nanananabooboo" variety web-speak), however I am curious, why exactly are you writing Science Fiction? This paper basically tells me one thing: do not read my books because, well, they are BS! I suspect you are simply flexing your intellect for such matters, but I am highly suspicious of any Science Fiction writer with such a hardboiled stance on the possibilities of the unknown. If this is the way you truly feel about the mysteries of the universe, then I might as well get my Sci-Fi fix from Dr. Phil, because, well, Charlie said that it was all bogus! None of it is real! Space travel? YOU MORON! Look at Charile's date. Why in the world would you read a fantasy book about something so outrageously impossible. Look at his data! Sci Fi is a joke! Charlie said so!


Forgive me if this argument has been addressed already. but all of the author's travel time information is based on current-day chemical rocket technology.

Travel times could be drastically reduced by using more advanced technology that is being developed by former astronaut Franklin Chang Diaz. His organization is working on plasma rockets that will substantially increase delta V, so speeds are increased and travel time reduced.



"On the plus side, if we see "Osama sitting up there in the moon broadcasting taunts, untouchable by anyone", then he and his followers can't touch us."

Ah... wrong. They very much could touch us. Or have you forgotten the premise for the success of the Loonies' revolt in Heinlein's The Moon is a Harsh Mistress? As David Weber puts it, he who controls the high orbitals controls the planet. Very good reason to make sure that no one group controls the Moon.

And on the other point, I am very much in favor of not putting all our eggs in one basket. Might be the difference between male and female thinking there.


"Space is big. You just won't believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space."




Bring back Project Orion


You can go to Dr. Michio Kaku at

He's already worked all the logistical and energy requirements for Types 1,2 and 3 civilizations.


Minor nitpicking:

We've sent space probes to Jupiter; they take two and a half years to get there if we send them on a straight Hohmann transfer orbit, but we can get there a bit faster using some fancy orbital mechanics. Neptune is still a stretch — only one spacecraft, Voyager 2, has made it out there so far.

This might be read by some people as implying that only Voyager 2 has gotten as far away from Earth as Neptune's orbit, when in fact four spacecraft have (Pioneers 10 and 11, Voyagers 1 and 2).

Also, note that the New Horizons spacecraft took just over a year to reach Jupiter. "Fancy orbital mechanics" isn't primarily useful for getting you somewhere quickly; it's useful for getting you somewhere at lower cost (e.g., via the Interplanetary Transport Network), with a tradeoff in increased travel time.


Charlie @86:

I think there are a couple of reasons why libertarians love the idea of space exploration. One is that they tend to be forward-thinging technophiles as individuals, they have a lot of faith in technology and don't tend to fear things like nanotech and cloning. Another is that they've idealized the American Frontier of the 19th century, a time when rugged individualists escaped the bonds of society, and they'd like to do that themselves in part. Of course, the only modern frontier is outer space, and never mind that early colonies are likely to need to be much more collectivist or corporate than any in the past. And the third reason is probably Robert Heinlein. I know I was exposed at a young age to a lot of libertarian ideas by reading his books, at the same time as I became enamored with space travel. All of us want to be characters in "The Moon is a Harsh Mistress".


So Proxima Centauri, at 267,000 AU, is just under two and a third kilometres, or two miles (in old money) away from us.

Perhaps a bit nitpicking, but 2 1/3km != 2 miles.


Um, might I suggest you stick to what you do "best", such as writing about ninjas?

And you aren't that skilled there, either.


My, don't the comments get rude when people's own little private beliefs get challenged?

What I see as a common theme is pure handwavium: " we don't have any solution now, but one just has to exist [because I want it to]". The appeal to previous intractable problems which were solved by new accesses of technical or scientific know;edge has the problem of assuming that all intractable problems are solvable a priori. It's rather like the claim that because some valid new discveries are greeted with derision, this idea which is greeted with derision must be a valid new discovery: "'They laughed at Marconi! They laughed at Edison! They Laughed at Einstein! They laughed at my Uncle Herbert...!' 'Your Uncle Herbert? But I ain't never heard of your Uncle Herbert!' 'Aha! That's because he was mad!'"

I also see some people who seem to have reading comprehension problems: Charlie isn't rejecting the idea of space exploration (via robot, principally); he's rejecting the probability of effective space colonization (absent magic wands).

Finally, of course, people also seem to be missing the point that, asinde from mundane SF and the like, SF is largely about magic wands...


Thomas @ 98 - BAHAHAHAHA. The comment to end all comments!


The problem is that so many previous pessimists have been proven wrong (ie. "railroads can never go faster than 30 mph", "I can only see a need for 10 computers in the world" etc.) If you can't see anything coming in the next 100 years that won't change something basic about space exploration, then I think you don't have enough imagination. And then it is a little bit strange to style yourself an SF writer.


Karl, the problem you suffer from is surviver bias. There have also been a lot of pessimists who were proven right, though nobody ever bothers to mention them. There seems to be no merit in predicting that something won't work, unless you provide a (working) solution along with it. And even then your solution has to be implemented.

In short, the existence of any number of pessimists who have been proven wrong, doesn't say anything about the quality of pessimistic predictions. (The same, of course, goes for optimistic ones.)


What I love about comment 98 is that it appears to come from someone who has read the Boing Boing story describing Charles as a badass ninja science fiction writer and assumed that he writes SF stories about ninjas. Then, he criticises Charles' writing immediately after making it obvious he hasn't in fact read any of it.


I was quite disappointed with your latest rant, it seems you must have had a very bad week and perhaps a brain tumor. How else to imagine why a science fiction author would so publicly, stridently and logically tear to shreds the hopes of anyone in space travel that you yourself have helped to kindle? And with such... zest?

This is diametrically opposed to the positive "can do" outlook of say for example Heinlein's protagonists. I'm talking about the Have Spacesuit Will Travel type. A young guy who understands analog circuitry and has memorized all the distances of the planets from Earth. Perhaps this is very difficult to imagine today though. Being hard-headed about scientific facts is one thing, saying there is nothing interesting in the Oort cloud, possibly the most fabulous dreamworld to explore in our solar system, is well almost a dirty lie. I think you do have an unshirkable responsibility to recognize that: 1) Expanding our frontiers has never been done by people who think like you, who spend their time saying why we must not hope to go. 2) The crazies who make it to the new world blaze a path and find reasons the slightly less crazy can use to rationalize greater investment and not listening to you. 3) The lack of obvious civilization throughout the galaxy points to a preponderance of people who think like you, whereas there is a big opportunity for people who don't think like you, per se. (They already can manipulate energy at that level you find borderline insane.) 4) If science fiction is anything but masturbation, it is a tool for conceptualizing about the future and what lies around the bend, in other words it is a bootstrapping enabler. It is entirely possible there is a beacon waiting in the Oort cloud to test if we are curious enough to find it, etc. Or more down to earth, satellites are of course the invention of a science fiction writer as you very well know.

So how do you explain the glee with which you apply your literary skillz to shooting down dreams of the future based on only the state of the art as of June 2007? I don't get you.

The problem is that your black humorless grimace seems designed to take the wind out of the sails of anyone who dares imagine such things, and I wonder why you do that.

To me it is quite simple what we need, why I have to tell a sci-fi author is beyond me. We need an absolute mastery of nanotechnology, materials science, artificial intelligence and scavenging of energy and mass first of all. This will enable us to live in the Gobi or anywhere we damn well please. Figure on at least the "seed" technology at the end of The Diamond Age, and them some. Between that, even just current space drives and Martin Lo's (of Genesis Project) gravitationally assisted trajectories ("superhighway") around the solar system we can colonise our own system. As for other stars, why worry about it for now.

By then we may be doing some weird uploading but somehow we'll be able to colonise the galaxy, even if only by robotic proxy and even if it takes millenia. Probably the concept of what "I" is will be quite different around then (if you listen to Moravec anyway).

As we build more and more of these diamond-studded palaces in the sky, sailing along gravity-free paths like so many soap bubbles on a winding stream, we will not be alone out there. We will be as close to our neighbors as the next bubble of life and we will foam out to the next star that way. People out there will not have the same values as you, but that's okay because it will be real for them too. Perhaps they will be constantly trading for new technologies to feed their replicators over broadband through the mesh created by this pseudopod of humanity. Maybe some will develop a more efficient propulsion method and choose to break off from the central limb of humanity to reach the next star faster, there to rejoin.

Here you go, Charlie, a new story and it doesn't really need much tech. It spells out exactly where to funnel our funding and hey when the Gobi desert starts looking inviting after a few hundred years of population growth maybe a magical palace in the sky won't seem too bad after all. Maybe you could write a researched platform for it and open it up to young scifi authors to cut their teeth on.

We need more kids (big and little) to absorb vast perspectives and faith in humanity and science, the kind only informed science fiction can provide. That you find your suburbs more inviting than some spartan spaceship is entirely understandable, unless you choose to imagine a comfortable one.

I only ask that you apply the same brains and talent you use writing fiction, to write non-fiction. Not this low-brow rant. Don't wave your hands at giant concepts by mentioning them as lone keywords while spending all your time explaining how the world is a big place. How about revising your goals to always create something profound and exhilirating, and if you don't have anything good to say on a particular day, save it and think about what you can do about it? Physics itself is grand but if you choose to keep your eyes at ant-level and interpreting physics with a similar perspective, there is no point to sharing your vision with the rest of us.

Thank you and keep up the good work. Hope you feel better next week!

Yours truly,

Matt Rosin Tokyo, Japan


I agree with 101. Necessity is the mother of invention and imagination is the key. It's ok for a Sci/Fi writer to explore the negative side of human nature with things like post-nuclear war earth and aliens taking us over, but never to crush our spirit and dreams.

There is no doubt in my mind that humans will populate the universe.

The reason I am so sure of this is because the quirky phenomenom of time dilation...

It's nature's way of providing access to the entire universe, in a single lifetime.

" For sufficiently high speeds the effect is dramatic. For example, one year of travel might correspond to ten years at home. Indeed, a constant 1 g acceleration would permit humans to travel as far as light has been able to since the big bang (some 13.7 billion light years) in one human lifetime. "

Just because the explorers/colonists will forever lose touch with people and society on the world they depart doesn't mean it can't be done, just that they need serious preparation for any eventuallity before they leave. I think this isolation will also help their chances for survival, one, because they begin their journey without safety nets they will use extreme caution and ingenuity to overcome hardships. Two, the isolation will allow them to grow in relative security from human agression. Also, by venturing out into the universe in stages, the task of deep space exploration becomes easier and easier. First stage would be to colonize the Moon, then Mars, then perhaps a few moons on Saturn or Jupiter, then hop to the nearest star, with all the equiptment necessary to set up shop on a planet or moons as we will with those in our solar system.

The ships wont need to be "generation ships" because at 1G constant acceration it will only be a few years at the most for any hop to another closest star. However they will need to be equipt as such since they will need to be self-sufficient/sustaining for many years even after they land.

Of course it isn't going to be easy, but I see our populationg the universe as inevitable.


I LOVE this site! Correct me if I am wrong Charlie but this was just a little essay you knocked up while you had a nasty head cold. A quick piece with some nice analogies and mathmatics. Well i liked it! I don't agree with all of it but the previous few people who are trying to start a flame war really need a sense of perspective. One of the areas you seemed to gloss over was the military aspect. I think lunar colonisation is inevitable from a strategic angle. (See #91 et al and Nivens Footfall). I can see some fun and games with an expansionist China and an increasingly conservative/broke USA setting off a 2nd space race culminating in a Lunar arms race. :(


I like the Moses approach. Wait until God say to do it, pick up a staff, get a crowd to follow you along, then just take off and rely on the Pillar of Fire to guide you and the manna to sustain you. All you science geeks are relying way too much on math and matter, and not enough on faith and courage.


Hmm... to those of you who feel your dreams are being crushed by Charlie's analysis, let me ask this... do you expect the hoped for solution to interstellar travel to be powered on hopes & dreams, or do you think it is will be a logical, scientific solution? If you think the former, then you should applaud and encourage people discussing and analyzing the aspects that seem to be insurmountable.

Also, I have to say (and this is my personal taste) that I think the best science fiction is really exploring issues (perhaps in the guise of aliens, spaceships, or whatever) that are relevant to our present life on Earth. SF that lives to be predictive tends to be a bit dead & pointless. So I think it's a bit silly to question Charlie's SF writing because he doesn't think the stories he writes are likely to ever come true.


I am so fricking confused by these comments. I can't tell whether people are being subtly snide, tongue-in-cheek, or genuinely believe it when they say it's "odd" for a science-fiction author to say that the economic reality of space travel is that it won't look like American colonization.

Thanks a lot, Cory. Charlie's forum has often been the site of colossal collisions of world view, but it's rarely been so ambiguous.


Why do libertarians [North American subtype invoked] and conservatives like space colonisation?

James Nicoll strikes. Here is the news, bub.

Charlie, I quite agree with most of your comments here, but I would like to pick up the North Atlantic one and run with it. Yes, people do go to sea, and they do a variety of things there of great economic value. Offshore oil rigs (and in the near future, gigawatt-scale wind power) are one. Ships are another - 90 per cent of international trade goes by sea.

From a literary viewpoint, the idea of a caste of hardhat space engineers who go out there for the money is not without possibilities (although Robert Heinlein copyrighted a lot of them). And the consensus of opinion here appears to be that the possible conquistadors of space are either mercenary aerospace engineers or crazy idealists. Well, a combination of skilled hardhats with an eye to the main chance and crazy idealists with their eyes on the stars gives any project a lot of delta-V, whether it be a shining city on a hill, a global computer internetworking protocol, or a pyramid of skulls - or some combination of those three.

I'd be remiss, by the way, if I didn't point out that the idea of a spacefaring society with a dangerous tendency to go postal with axes is a pretty obvious satire of a certain nation not a million miles from the North Atlantic..


You seem to be ignoring the use of extraterrestrial resources. I have some comments.


I am so fricking confused by these comments. I can't tell whether people are being subtly snide, tongue-in-cheek, or genuinely believe it when they say it's "odd" for a science-fiction author to say that the economic reality of space travel is that it won't look like American colonization.

They have been trolled by a master. It is a thing of beauty.


" Hmm... to those of you who feel your dreams are being crushed by Charlie's analysis, let me ask this... do you expect the hoped for solution to interstellar travel to be powered on hopes & dreams, or do you think it is will be a logical, scientific solution? If you think the former, then you should applaud and encourage people discussing and analyzing the aspects that seem to be insurmountable. "

Actually, I was refering to Charlie's fictitious future human population, but the same could be said for people who limit their edification on the subject to Charlie's rant.

I agree, this is a worthwhile discussion, I just wish Carl Sagan were here to set charlie straight on a few things!



Putting people on planets may take a while but several comments have rightly mentioned terraforming. Synthetic biology will take us in this direction. Without the human element it may be less than fertile territory for sci-fi, but it's still interesting to think about how long it would take to smother a big asteroid in radiophilic bacteria and fungi (like D.radiodurans) and whether/how you could actually tweak a climate this way.


I think Charlie's science is pretty solid. But the things that he dismissively waves away as "magic wands" are what science fiction authors would call "technological advancements."

Really, it's just an energy problem. With enough energy we can overcome all the other issues. I don't mean it's guaranteed to happen; we may never be able to produce that kind of energy. But from a science fiction author's point of view, it's at least plausible, and that's all you need to write a story.

I have a fuller discussion here.


Matt @105: was quite disappointed with your latest rant, it seems you must have had a very bad week and perhaps a brain tumor. How else to imagine why a science fiction author would so publicly, stridently and logically tear to shreds the hopes of anyone in space travel that you yourself have helped to kindle? And with such... zest?

... Because I dislike willful ignorance and I hate being told comforting lies.

In a nutshell -- and my third [non-introductory] paragraph should have been a honking great flashing neon Time Square sized sign -- the space settler enthusiasts have basically swallowed a cartload of ideologically weighted propaganda, cunningly combined with emotive appeals to abstract (and thus unfalsifiable) ideals. Your use of the phrase "the high frontier" is itself a telling one -- and you use the term "frontier" repeatedly. Then you start going on about indoctrinating impressionable young minds to "absorb vast perspectives and faith in humanity and science" as if you think I've got some quasi-mystical duty to teach Ideologically Correct Gerard K. O'Neil Thought, and by implication, any kid who doesn't buy what is effectively a collectivist pie-in-the-sky daydream is deficient, unimaginative, and foolish, and any SF writer who refuses to pander to this political creed is evil and wrong.

I don't like being told what thoughts I'm allowed to hint. I like to question assumptions. And this is just the result of my interrogating some of the assumptions underlying space opera, using the toolkit of Hard Science Fiction -- i.e., trust the numbers. You can take it as a default likely outcome, if certain normative conditions hold true: that is, if there is no AI singularity, if there are no breakthroughs in fundamental physics, and if Drexlerian nanotechnology and molecular genetics don't give us the tools to transform our bodies.

There is no guarantee that one or more of those things are not going to happen, in which case all bets are off and we probably ar going to find that interstellar colonization is a tractable problem; but equally strongly, I'm not placing any bets on the eStandard Model of physics being found to be so strongly broken that two-fisted engineers are building FTL drives or fusion reactors in their basements a year later, or on us all going a-flying up to upload AI heaven.

Bill @106: I suspect the "spirit and dreams" to which you allude are the product of extensive political indoctrination. Please start to consider your starting assumptions? It hurts at first, but at least once you've done it you'll know where you stand.

Toadlicker @107: yeah, I just knocked it up yesterday because I was feeling too crap to work on the current novel. Your point about the moon and militarisation of space makes sense, assuming the current superpower competition model persists for long enough with enough surplus money behind it to make the use of the moon viable. (There are some technical issues to do with what you can use the moon for that need to be questioned -- using it to base missiles, other than a "second strike" capability, is reeeeeal dumb, their rocket plumes can be seen from Earth with a rather small telescope and the warheads would take days to arrive -- but for other purposes such as observation it'd be really useful.)

Michael @110: the sad thing is, I think a whole lot of them really believe it. As in, they believe. It's not rationally grounded optimism with an underpinning of facts, it's religion in disguise.

Rand @112: yep, in situ resource utilization would really help. The "live off the land" Mars expedition ideas that Zubrin hatched, and the idea of synthesizing fuel for a return journey from the Martian atmosphere, is so obviously sensible that I have difficulty believing anyone's looking at plans for Mars missions that don't rely on them. On the other hand, there's one big problem with ISRU; namely, demand for the extracted resources versus the cost of shipping the extraction plant up there in the first place. ISRU only really makes sense when it's cheaper to ship, say, a 100 ton extraction plant to the lunar surface, than to ship 100 tons of pre-processed raw fuel/material from Earth. As part of an actual industrial cycle it's a good idea, but I suspect we've got a long way to go in developing self-contained fabrication systems (and mining/extraction systems to supply them with feedstock!) before we're there. Even worse, here on earth we don't actually need self-contained ISRU systems -- we have a global economy to plug into. So the cost of building such a system is probably going to be high because you've got to go all the way to a fully working one in a single bound, rather than having useful intermediate technologies you can market along the way.

Adrian @113: have a cigar. You called me on it, and you called right. Thank you! :)


You are no longer invited to consume vitamin pills at my moon base. :(


So the cost of building such a system is probably going to be high because you've got to go all the way to a fully working one in a single bound, rather than having useful intermediate technologies you can market along the way.

Ah, that's what I call "creationist technology".


Alex @119: doesn't mean it's impossible, but it's the same reason "Fusion is Just Fifty Years Away" has been the slogan for the past ... fifty years.

And what really annoys me is when someone takes a good idea that has viable intermediate tech spin-offs, and tries to go for the money shot in one move, and falls flat on their face.

If the folks at Liftport had focussed on simply making stronger, longer fullerene cables and tapes, then selling them for terrestrial construction projects (to fund developing fullerene cables that are even longer and much stronger -- rinse, cycle, repeat) we might be well on the way to having materials that have the tensile strength necessary for a space elevator by now. There's always a market for a better suspension bridge cable, after all. But my understanding is that they focussed on going straight to the elevator, assumed high-tensile fullerene tapes would come along anyway, took a bite at building a climber along the way ... and are teetering on the edge of going bust.


I read what the required strength/weight ratio for a space elevator cable was pretty close to the theoretical limit for carbon nanotubes. Never going to get me up in one of those.


Karl, I don't think Charlie (or anyone else) doubts that new basic science, sooner or later, will yield something that could provide a "magic wand." Maybe on-beyond-nuclear (but easier to manage) energy densities; maybe on-beyond-GR reimagining of spacetime; maybe -- as in the starwisp/upload route -- a change in what we mean by "us" and by "being there" so complete that the idea of shipping meat with life support becomes laughable.

It's simply that by the very nature of such radical departures, the result won't look much like any extrapolation of the technologies we have. So -- at least in technology-projection, R&D-steering mode rather than SFnal mode -- it's hard to say anything concrete enough to be interesting. For all the talk of Columbus, at the moment we're really more like Phoenician coastal sailors guessing at how many shifts of oarsmen it will take to row west to the Land of Jade.


So exactly which idealogically weighted load of bollocks would you prefer that we all subscribe to? Your article hammers pretty hard at the foundations of the shaky edifice of space exploration, but offers little suggestion of what we should build among the rubble you left behind.

Many of the yay-saying posters here seem to echo that depressingly small-minded camp that trumpets the equally vain assertion that we must solve our problems here before reaching for the stars. Given that thousands of years of human history have been inadequate to slay even one of the four horsemen, I doubt that is any more rational a hope than attempting to leave them behind on our shiny rockets.

Frankly, I think the only cure for the human condition is for the species to step aside and make way for the next step in evolution undoubtably brewing in some illegally run lab somewhere.

Until that grim day, I see no harm in reaching for the stars, and swallowing whatever gentle lies the visionaries of our culture tell us to motivate the movers and shakers to open their wallets. I certainly prefer these lies to the ridiculous scenarios for a better world spewing forth from the lips of holy rollers and Kalishnikov-weilding madmen. And, as pointed out already, there is some practical value in holding the high ground in our own terrestial disputes.

It may be a longer journey than most people imagine, but whining about how long it takes to get there is about as conducive to a pleasant trip as that small, relentless voice in the back seat endlessly repeating "Are we there yet? Are we there yet?"

Don't make me turn this thing around...


Isn't it possible to get up to several percent of c using a solar sail? And of course, if you accelerated using a solar wind, you can decelerate the same way...


Creationist tech, Charlie, by reference to this post.


One of the reasons we haven't colonized the Gobi Desert is that there aren't enough people already there to effectively exploit. If there were a population of indigenous Gobians who had figured out how to live there comfortably and extract wealth from the landscape, they would have been overrun centuries ago, regardless of the geography.

If you look at the history of human colonization (as distinct from human migration), colonies are successful when there's an existing human presence (technologies, infrastructure, agriculture, labor) to leverage. Human beings don't colonize uninhabited places.*

I suspect that the economics of space colonization could change radically if there were alien civilizations out there whose technology and infrastructure we could exploit. And I have no doubt but that ethical objections would never come up.

  • I'm going to assume that the atmosphere is an effective barrier to further migration, leaving colonization the only option. I don't see us moving into space gradually by way of trading posts in the stratosphere.

** Ignoring, of course, the many Great National Myths.


Actually, we could send a manned expedition to the Centauri system "today," provided we had the determination to do so. The basic science is already done, and all that is left to do is gather the resources and do the greatest engineering job in history.

The big questions are, do we have the will, individually and collectively, and is there a desirable destination for us at the end of the trip.

I'm in favor of starting, sometime in this decade, to design a robot probe to try to find the answer to the second part of the question.

I suspect the occurence of terrestrial planets in proper orbits necessary to support our sort of life is actually quite rare, and the "Hot Jupiter" scenario is pretty much the norm. But, that shouldn't keep us from looking, because we are a curious sort of monkey and that may be a species imperative.


The main problem with this is, to paraphrase Chris Peterson, a future with nanotech and AI may seem like science fiction, but one without them is just fantasy. I've written a book on each subject ("Nanofuture" and "Beyond AI" respectively -- Charlie, check out the latter, you're quoted in it) so I won't go over the arguments yet again.

One point, tho: the trend line for air-travel speed rose exponentially till about 1970 and then levelled off -- for economic reasons, not technical. (Going Mach 1.1 costs 3x going 0.9) But the energy cost of NYC-Sydney is the same in a 747 or orbit. So there's a chance that orbital travel will pick up when the underlying tech curve, projected from the original, would have hit orbital velocity. That turns out to be roughly 2010. Current developments are possibly promising.


If there were a population of indigenous Gobians who had figured out how to live there comfortably and extract wealth from the landscape, they would have been overrun centuries ago, regardless of the geography.

They're called Mongols and they had a leader name of Genghiz Khan...


Charlie sez: I suspect we've got a long way to go in developing self-contained fabrication systems (and mining/extraction systems to supply them with feedstock!)...

To get a bit more -- ahem -- granular, NB the big difference between all-fluid-phase processes, such as Zubrin's scheme for fuel and O2, and anything that handles crunchy, inhomogeneous solids.

For the former, the feedstock is ambient and all you need are highly reliable pumps and valves. We're pretty good at that.

For the latter -- excavating, transporting, crushing, sorting, etc. -- the only way to get long, unattended uptime is very heavy components driven by very large, dependable power sources to simply grind through jams and friction. When people tell me about a handful of astronauts and a few tens of tons of equipment starting an ISRU bootstrap for lunar cinder blocks -- let alone solar cells or linac components -- I know they've never seen a mine, cement works or gravel pit starting up.


It seems to me Columbus would have had the same arguements about a trip to the moon as Mr. Stross. The same could be said about Neolithic man thinking of Columbus's voyage.

The problem here is contemporary thinking about technological structures of the future. If the distances and energy requirements of space flight seems daunting, it is because we think of such things in terms of the limit of our current necessities and abilities. .


Alex, I'm not sure that the Mongols lived in the desert so much as exercised political control over it; I thought their ancestral home was more in the grasslands to the north. And they were fairly strapped for natural resources as I recall; they took some rather extreme measures to address that. But I grant you I could've come up with a better example.

In any event, maybe a better counterexample would be the Silk Road, when parts of the Gobi were well-populated and civilized. However, when better trade alternatives became available, the cities dried up (no pun intended).

The Silk Road kinda reminds me of all that Golden Age SF about the Romance of the Spaceways. In any event, a bad, limited analogy is tangential to the discussion.


Barry @123: Okay, so you want a space program? :)

  • Get dug in for the long slog. It's not going to take decades. It's not even going to take centuries. If you want it, you've got to accept that grabbing hold of the universe is going to be a background task for countless millennia to come. Corollaries:
  • a. Pay some attention to how we're going to survive the next century, pollution, resource depletion, climactic anomalies, and all.

    b. Start looking for a sustainable philosophy that doesn't rely on unstable indefinite consumption growth or jam-tomorrow quasi-theological arguments, but that can still provide a motivation for your n'th generation descendants -- who may resemble you, culturally and emotionally, as much as you resemble an Aztec high priest -- to persist with the same grand project. (I'll add this as a rider: interstellar colonization is profoundly counter-utilitarian, to such a degree that I'm astonished that libertarians or free-market capitalists will give it the time of day. You need to learn to live with the expectation of zero return on investment, if you want to give it your best shot.)

    c. All national myths are soluble in deep historical time. So basing such a philosophy on a national myth of frontier expansion is ... silly and short-sighted. Time to grow up, stop looking for the Wild West, and realize that any successful interplanetary or interstellar enterprise is going to be a gigantic collective endeavour, not the domain of mavericks.

    (Are we gagging yet?)

    Now for some minor implementation details.

  • Fixing humans to live in a new environment is easier than changing the environment to support humans -- at least, when the environment is as hostile to biological life as the rest of the solar system. So: pursue biological engineering. Pursue tissue engineering. Pursue medical nanotech. Pursue endosymbionts and artificial organism research. Accept that Homo Sapiens Sapiens will probably never go to the stars, but beings recognizable as our children might be able to. (NB: I'm not ruling out those vacations on the moon -- just saying that long-term colonization, especially at long distances, will require adaptations so radical we may effectively end up with another species.)

  • Tech that isn't ruled out and that might make the whole interstellar colonization shtick practical is on the horizon: mind uploading, AI, starwisps, tools for fabricating replicas of human bodies and downloading neural network maps into them. But this stuff is not guaranteed, and some or all of it may never show up. Learn to be pragmatic, and work with what's available.

  • ... How's that for a start?

    Josh @127: I'd like to believe that the reason EADS just announced they were sinking €1Bn into developing a sub-orbital puddle jumper is because long term they're thinking about ballistic sub-orbital liners, for exactly that reason. On the other hand, I'd like you to take a moment to ponder the political (read: anti-terrorist, not to mention anti-covert-nuclear-strike with ICBM disguised as sub-orbital bizjet) implementation headaches surrounding such a development. Betcha the super-rich and the heads of state get their sub-orbital spaceplanes while we're still slogging along in A380s ...


    It's likely there'll be a sufficient (for someone) ideological payoff for a Mars colony: "Quick let's get there before the Chinese". But after the payoff loses its lustre, I imagine a rather unkempt small slum of too depressed to be terrified young post-docs to whom the Gobi will look pretty good. After the first televised die-off, however, we'll "bring the boys back home," too discouraged to give it another go until the magic wand shows up. Write me one, will you Charlie? My magic wand faith needs a boost.


    Where have you been hiding these ninja stories, Charlie? Are they part of your Clan Corporate series?*

    As for this post, aside from the obvious troll-baiting, it looks like a necessary bit of foundation-digging for some new stories. Given this, that, and the other thing, what magic wands will you need to have in your stories to make them work?

    • :)

    It occurs to me that Accelerando has the same theme as this article - an explanation for the Fermi paradox. The argument is also the same - we are already very comfortable at home, there is no reason for traveling into an inhospitable environment.

    Yet in the same novel we have refugees fleeing the singularity to another star system.

    With inevitable improvements in robotics (see Asmino, Darpa grand challenge) I really dont see why our robotic emissaries cant precede us and prepare an environment suitable for us.

    Sometimes the whole point of leaving home comforts is not being at home anymore.


    NelC: it's a spin-off of the foundation digging for my current novel-in-progress ... a space opera.

    (Yes, I'm a masochist.)


    It's just a liar working for George W. Bush, ehem, private personal chief of Bush?.

    Many attempts recoinnanssing the Mars and Moon for future colonization. Not the colonization of today.



    I, for one, welcome our new, Slashdot-wielding masters ...

    ("Second slashdotting in 34 days? The server cannae handle it, cap'n!")


    "If you want it, you've got to accept that grabbing hold of the universe is going to be a background task for countless millennia to come." -133

    How is this a problem? It seems to me it is just a extension of what humans have been doing all along. In that respect, we have been at it for millenia already.

    On point 2., I agree humans will be modified before we attempt interstellar travel. You forgot immortality on your list. .


    The robotic emissaries thing ends up, though, with Stephen Baxter's Sheena - they decide to keep going, and forget about us. There is, however, an escape hatch - Sheena the talking squid and all her kids' artificially instilled English. If nothing else, our language is going to the stars.

    In a sense this is very much a post-WW2 British vision - we may have lost the empire, but we've gained some damn good books!


    " Bill @106: I suspect the "spirit and dreams" to which you allude are the product of extensive political indoctrination. Please start to consider your starting assumptions? It hurts at first, but at least once you've done it you'll know where you stand. "

    Well, if I were a right-winger that may hold true. But I am Thom Hartmann's (the guy who took Al Franken's place on Air America and author of many VERY liberal bestsellers) moderator at I saw how the race for space bolstered the economy, just like a war does, only without the death and destruction.

    The spirit I speak of is real and although the right has hijacked it in the past as something of their own design, it really has nothing to do with ideology. I think it's just an inner drive to satisfy an insatiable curiosity and a need to alway be expanding our horizons.


    Charles : There IS a way to solve this energy problem. It's pathetically easy, and requires no magic wands. I am surprised you haven't considered the approach.

    Idea One : The biggest problem is that the standard "rocket equation" has some logarithms in it. That means when you scale up to the energy requirements for an interstellar jaunt, you end up with all sorts of nasty requirements for the Isp of the engine. If you have to carry all your fuel with you, and your reaction mass, you aren't going to get there in time.

    So, you don't carry it, and you don't use a laser, because a laser beam's intensity diminishes with the square of the distance. You use a beam of 'smart pebbles', launched from a big accelerator. The pebbles have iron in them, and the starship is a very long and skinny stack of superconducting magnet rings, with some type of energy storage accumulators. Momentum transfer. To slow down, you throw half the spaceship away. (am summarizing because I want you to read this)

    Idea Two : How do you get the industry to support it? Well, as I see it, there are just 2 parts. The solar array with the surface area of the earth, to supply energy, and a relativistic accelerator thousands of kilometers long. Oh, and the plant that makes the pebbles atom by atom, as they are packed with molecular scale circuitry and thrusters.

    Well, that's easy. Really. After all, you have already posited that the explorers have the "military industrial complex in a can". And, when I wrote this up a while back, I had the payload mass of the spaceship at 100 metric tons, and the total mass including engine at 1000-2000 metric tons. (there is a LOT of spare mass, to make up for deterioration from particle impacts)

    So, you land one of these "military industrial complexes" on the moon. It might weigh 100,000 tons, who cares. It's a factory large enough to both replicate all of the parts in itself, as well as make segments for the solar arrays and launch accelerator. It sends out mining machines that scrape off lunar regolith, it does a ton of processing on the raw materials to make them into parts, and it receives power beamed down from space. It packs the products into capsules that get loaded onto a magnetic accelerator.

    Realistically, the factory is as automated as human software can make it, and the slack taken up by teleoperators working for cheap.

    The spacecraft goes to 0.9c, no wimpy 0.1c.

    But no, I don't realistically think a human being will ever be stuffed into a vehicle like this, or that human attainable industry will ever have enough resources.


    I think if there must be a space exploration/settlement than it should not be in our solar system because i see the only reason the leave earth in the estimated burnout/growth of the sun in a few billion years, well maybe thats a litte far away to think about ;-)


    What is strange to me here: O'Neill is mentioned, but the implications of the kinds of space settlement he proposes aren't really discussed. If you have a settlement of the asteroid belt like O'Neil proposed, at the end of the process humanity will be much larger and much more diverse.

    Settlement of other start systems is a long term project. However, I find it conceivable that if the asteroid belt were settled, some of those folks might be inclined to take on a long term project.

    Would it be worth a few thousands of dollars for someone to send a sperm or ova sample on a robotic ship knowing that it might attempt to create an outpost of humanity 500-1000 years in the future?


    Just a couple of random thoughts -

    1) How much energy could we pick up en-route using slingshot type techniques?

    2) No current Earth government would supply funds for a self sufficient colony that it could by definition not have any control over (unless it resorted to serious mind bending on the colonists)


    130: No, Columbus didn't face those kinds of arguments. The benefits of trade with Asia were known. A short, ocean route to Asia would have been a great coup for Spain. It would eliminate the middlemen and cut transportation costs. Isabella calculated that the benefits of success outweighed the risk of failure. The fact that it turned out several orders of magnitude better for Spain than could have been predicted doesn't mean that the original business proposition didn't have merit on its own. (It's worth noting, too, that within fairly short order, Spain established the transpacific Manila-Acapulco trade route. They never forgot their original goal.)

    Columbus was seeking a shorter route to trade with people that he already knew existed. He wasn't sailing into the unknown; he was sailing to a known place with a bad map. He made a serendipitous mistake at a propitious time for Europe.

    Is it possible for humans to wander off into deep space with no clear hope for success and then stumble onto something that makes it all worthwhile? Sure, but you can't plan for it. It's like charging off into a land war in Asia in the hopes that a miracle will occur.

    I really think that the discovery of intelligent life in outer space is a necessary precondition for any hope of humans moving into space. I'll say it again: Humans don't colonize places that don't already have people living in them.


    122: Well, we didn't go to the moon in a big cannon either. That's the problem with extrapolation: it doesn't work. It can produce interesting comments on the present (and IHMO this is a large part of the purpose of good SF), but it will not predict the future. Granted, it is damned hard to predict the future, because new basic technologies will appear, and some problems will prove harder to solve than we think (the common cold). Maybe space travel is in the latter category, but I wouldn't bet on it.

    I think the biggest obstruction to space travel is in political will. Look at what was accomplished between 1958 and 1968 and what has been accomplished between 1969 and 2007. Depressing. Now, if somebody figured out that the sun would nova in 50 years, the situation would be very different...


    This article overlooks the likely path for future colonization because it takes a very sentimental view of what it is to be human. The definition of human is always changing even in our present compared to years ago (remember when dark skinned people were not considered human?). When we merge with our technology to achieve a hybrid highly evolved society the barriers described become much less problematic. Travel to an actual other star will not be necessary if I can beam the information that comprises myself across the galaxy using quantum communication systems. Cyborg entities are the likely future followed by a fusion of DNA and silicon though there will be splits between those who want to remain "pure" (organic human) and those who follow the above path. Hopefully that diversity won't lead to outright war.


    I am surprised that my ecological remarks haven't drawn more attention from anyone except, I think, our host. But I think it's a key point and one that people with mainstream engineering orientations tend to miss (happy exception: Robert Heinlein): Earth seems to be the ecological powerhouse of the solar system (unless life turns up on one of the moons of the gas giants, or on one of the gas giants themselves) and so I think Earth is going to be very important to any future human expansion into space.

    Barry, #123: the reality is, if we don't preserve the earth's ecosystems, we won't make it through the first centuries in space. So we have to do both.

    Josh, #128: nanotech is going to look like biotech, not 19th or 20th century engineering. (You heard it here, first.) It follows that cultural and economic models intended to exploit industrial technology are not appropriate to nanotech--it may be that the agrarian hippies win this one. (Awful, isn't it?) AI is unlikely to succeed until we discover a magic wand. It's very clear at this point that we are missing some key insight or technology; we don't seem to be making any better a job of it than the old-time magicians.


    "AI is unlikely to succeed until we discover a magic wand."

    Ummm, what? How much do you know about AI research? .


    Uhh...for the most part, we aren't DOING very much AI researcher.

    REAL AI would have to work just like our brains. We would first need to map out the 'rules' subsections of neurons use to wire themselves up. This will take a lot more research than has already been done, but there are tons of analytical techniques that will work.

    Second, we would have to build equivalent hardware using our electronic parts. That means programming a bunch of FPGAs to act like a brain, or using ASICs. As I recall, there are about 100 billion neurons, and each one may have as many as 10,000 synapses. So the memory requirements are only reached by large supercomputer today, and those machines don't have their circuits arranged in the right way for implementing a neural net.

    There's maybe 1000 people on the planet actually working on the above approach. Probably a lot less. (I am throwing in grad students and basically "everyone" who might be involved)


    If microbes had the same attitude as you, life on Earth would not exist. You think a couple of decades is a problem? Try 4 billion years. You think a couple miles to us is a problem... and we are 6 feet tall? How about being a couple dozen nanometers wide, and then trying to colonize a spherical object that is 510 million square kilometers.

    The point of colonization might be to benefit the 'mother nation', but as we have seen in history, colonies tend to take on a life of their own, regardless of mother's fate. And in the end, it is not the mother nation that spreads, it is life itself.

    As we have also seen, you basically cannot stop exploration and spreading of life. That's just what life does. It's like trying to stop the energy coming out of the sun.


    Karl: to take you literally for a moment, if the sun was going to go nova in 50 years (it can't, and won't), basically we'd be a footnote. Some reading up on the amount of energy released in a nova would be useful: read this paper, then bear in mind that even at the orbital radius of Neptune, the neutrino flux alone would be enough to give you a cumulative radiation dose of >10 Greys -- and neutrinos are so penetrating that even hiding behind that gas giant wouldn't measurably reduce your dose. Bluntly, the only way to survive a supernova is to be several light years -- minimum -- away from it when it happens. (Remember that scale factor analogy of mine? Supernovae are naked-eye visible at a million light years. That is to say, on that scale of mine where the sun and earth are one centimetre apart, and Proxima Centauri is 2.3 kilometres away, a supernova has roughly the destructive radius of a half-megaton ICBM warhead.)

    I agree that political will is an important factor, and right now it's lacking. But let's not forget the fundamental physics, shall we?

    GS @149: I was deliberately ignoring discussion of that topic because, ahem, I wrote a novel about it a couple of years ago (title is Accelerando, it got shortlisted for a Hugo award, and there's a Creative Commons download of it at the far end of that URL).

    Redratio @151: ""The question of whether a computer can think is no more interesting than the question of whether a submarine can swim" -- Edsger Dijkstra.

    Don Anonymous @152: you anthropomorphize microbes? It's no wonder you seem to think it's our manifest destiny to emulate a yeast culture on a galactic scale.


    Dumb article: I think there is a world market for maybe five computers

    The only analogy to this article is a caveman saying how it is impossible to travel from Africa to USA. The article is primarily an exercise in math based on current scientific knowledge.

    Humans may or may not colonize space - but to deduce either based on current knowledge is the equivalent of Thomas Watson saying "I think there is a world market for maybe five computers".


    Which is only to say that it's a falsifiable prediction. After all, Watson said that in, what, 1943? And how many computers were knocking about then?


    Charlie, I said a nova, not a supernova. The difference is quite substantial. Clarke's "Songs of Distant Earth" was based on this premise. I'm sure that there are several things that can happen to a star which are less destructive than a supernova, but destructive enough to take out the inner solar system (very aggressive flares, unstability, who knows). I do read a lot of stellar astronomy BTW, but I think that we need to be careful in thinking that we know exactly how the Sun will evolve.

    Vivek: This is what I am trying to say. It is supremely arrogant to think that we at this point in time have managed to expand our knowledge to the point that no fundamental new things can be discovered. There was one guy a couple of years ago that predicted "The end of Science". The same argument has been made endlessly over the ages, it is second only to predictions of Armageddon. Both are always wrong. We have just started our journey. Just like the solar system is a speck of dust compared to the cosmos, our current scientific knowledge is a grain of sand on a vast beach compared to all scientific knowledge that can be discovered.


    redratio1, #151: I majored in "computer science" as an undergrad, so I know AI as a related field. AI has been a serious research topic in modern computing for decades, and we're not any closer to cracking the big problems of AI than we were at the beginning of the project, despite vastly improved hardware. The failures have been enormously valuable; the greats of the field have worked on the problem and we've gotten a lot of useful technology from the effort. But--natural language recognition? personality? anything like human understanding? Not even close. So I think we're missing some crucial insight or technology.

    Charlie, #154: on the other hand, airplanes can fly. So I think that Dijkstra quote "sounds nice, but doesn't tie you down to meaning anything."


    I think this lacks imagination and underestimates humans. You put some facts on the table that are undisputed. But you miss the real incentive to colonize: we have run out of room here. Suppose we took a century to build a ship that could carry 5 billion people. Maybe it is a ring a thousand miles in diameter and perhaps a hundred miles wide. Then, instead of taking 450 years to reach a destination, they take much longer. But the destination is not really the point. I am not sure what the limit to gravitational momentum transfer is, but if you are patient enough, you can steal quite a bit of speed from the planets. (but I am sure that you can NOT get anywhere near 1% of c).

    There are four requirements for building these kinds of space habitats: 1) Technology, 2) energy, 3)material and 4) wealth.

    Who can say that the technology won't be developed? That is the easiest part to believe in. 2) Energy to power the thing is more speculative. But if we don't solve that particular problem, we won't be around in a thousand years in any great numbers even here on mother earth. 3) Clearly, the moon is the best source for materials. Perhaps we can raid the asteroid belt with some future technology. 4)wealth. We have to be a lot richer than we are now.

    Personally, I think it will take 10k years or so, but simply off loading billions of people from earth will be reason enough. Space exploration is simply a way to get the hell out of Dodge. Mankind is dangerous in large numbers. Suppose we produce one of these ships every 500 years or so. That makes earth sustainable and it colonizes space. In a million years, every sun in the Milky Way would have thousands of ring ships. So we not only colonize space, we fill up the galaxy in the blink of an eye.

    But, this is also an argument for the Fermi paradox. Which is why I don't think there is intelligent life out there. If we do figure out how to colonize, then the Milky Way will fill up fast. Then we will set off for other galaxies.


    So your saying there'll need to be a breakthrough in technology (due to a breakthrough in our understanding of physics) to make this possible.

    Your basically assuming that our understanding of physics will never progress to a point where the distances have to be travelled. not to sound too rude but that is short sighted for an SF writer.


    Unimaginative minds are doomed to be unimaginative.

    This argument is easily dismissed, IMHO. First off a number of premises must be made. And a number of associations taken for granted.

    I. That travel by sea to continents which took months as compared to travel in space taking years is drastically different.

    This is not necessarily the case due to the increase in knowledge. See those few month voyages were much more difficult than a longer voyage would be today due to our knowledge of medicine, diseases, health, etc. Much of the loss and death at sea was due to health and not travelling.

    That said, a 20 yr journey would be quite hard and difficult and require immense planning and good equipment. But let's look at the journey to Australia in 1600 versus 1800 versus 1950 versus modern day.

    In the 1600's it was nigh impossible with the technology available. In the 1800's it was difficult but possible. Took quite some time. In the 1950's it was relatively easy and safe. Still took time but nothing like before. Now in present day you can be in Australia safely in one day's travel. WHY?

    "Technological Advancement"

    The other premise the author relies upon is the inability to travel at or even faster than light. Now this may be accepted understanding than many. And though it may not be possible to travel faster than light in a normal real-time/space environment. I am one who believes such likely to be possible via other means. Be it dimensional hyperspace, or quantum entanglement molecular reconstruction. Who knows....

    But most of what we do every day in travel and leisure would have been considered impossible 500 yrs ago. And was, due to lack of knowledge.

    I always find it arrogant of scientists to believe they "know it all" and to exclaim impossibility for the future merely because of their lack of knowledge and understanding.

    So what if habitable planets are 100 yrs away. Given time, man will find a way. We always have....


    To quote the immortal words of Douglas Adams:

    The simple truth is that interstellar distances will not fit into the human imagination. -The Hitchhiker's Guide to the Galaxy


    Rolls eyes

    David Taylor, Jason the Saj, George Burt et al, I'm talking to you, among others:



    The Mgmt.

    PS: for those who don't know who I am, you might want to google my name in the context of "singularity". Note also that these days I get book blurbs from Vernor Vinge, and vice versa.

    PPS: Alex @164, we have just been slashdotted and comments are rolling in so fast and I have gained so much momentum in responding to them that I am now violating causality, traveling backwards in time, and responding to your comments before you make them. Thus, we have gone outside the light cone! FTL must be possible, after all!


    Come on, this is all backing off into non-falsifiable handwaving. If you think we're going to do, when, where, and how?


    Rather than merely throwing one's hands up in the air and saying "it's too expensive, so it won't happen", which I think we all knew, isn't it more interesting to ask when it will no longer be too expensive? What was the cost of producing 2e18 joules in 1000 AD? 1900 AD? 2000 AD? Restricting ourselves to the post-Edison era, from 1882 to date, I observe that one man-year of US per-capita GDP will buy an exponentially increasing amount of energy:

    yearMWh/man-year 1882 1 1900 2 1932 8 1941 26 1960 114 1970 231 2005 442

    Thus, it requires 1.25 million man-years of economic output to send your capsule load to the stars today. But in 100 years, it may take 3000 or less, and in 500 years it should be easily within the entertainment budget of a single household.

    Of course past history is no guarantee of future performance!


    While there certainly are obvious limitations in today's technology and hindrances imposed by petty politics, it's foolish to declare something impossible when the event itself is not something that you will be able to witness in your lifetime, or even in the lifetimes of your descendants. Who's to say that humanity won't develop the necessary technology for colonisation a thousand years for now? Or that we won't wipe outselves off the face of the planet before then?

    I think you should leave the business of predicting the future to prophets and madmen. There's no point in being browbeat over a subject that you have no means of proving or disproving.


    Aminorex, I have observed that the mean temperature in southern England has risen steadily since January, as the days have become longer. Should current trends continue, I predict that the area will be uninhabitable and in constant daylight by this time next year. Clearly, we must immediately set about the evacuation of London.


    Aminorex @165: I'd love to see you extrapolate that curve until we get to see one man-year buy us a supernova's worth of energy -- never mind the galaxy, we're going to light up the entire cosmos!


    Great essay! Well, there really is no need to despair of ever visiting the star systems of the Milky Way and even the galaxies beyond in your lifetimes, just because they are too far away. If those lazy-minded physicists of ours would only get their heads out of their asses, they would have figured out by now that space (distance) is an illusion of perception. In the not too distant future, we will have long distance jump technologies that will allow us to move from anywhere to anywhere almost instantly. Too far-fetched, you say? Well, evidence for the feasibility of long distance jumps has already been observed. It's called quantum tunneling. Why is distance an illusion, you ask? It's all explained at the link below:

    Nasty Little Truth About Space



    I think Robert A. Heinlein already answered this question. I think it was in "Expanded Universe" he explained the situation. The current methods we use to move spacecraft amount to the equivalent of floating a raft downstream using the force of the river. Given some changes in how we move craft - and he gives some not very difficult methods - and we can get year 1600s level transport speeds to colonies, e.g. 9 month trips to nearby planets. Which was the general time range involved in the plymouth colony, and potentially a few others. And the investors got rich on the trips.

    Current technology does not provide for a fully reusable "savable" rocket system. The Space Shuttle, in terms of reusability is a joke. Basically, the estimates are that a private organization could develop the technology to provide a savable reusable off-earth transport system, whether it's rockets or what not, for what was then $200,000,000 in the 1970s.

    Basically, a private organization could have created some form of reusable rocket for escape-velocity transport for about what it cost to create Biosphere in Arizona. (I presume, too many government regulations and politics to be able to do it by a government organization.)

    The microprocessor was a direct result of space-technology spinoffs. And many others; some of the developments will have real-world uses beyond the original design.

    And whether people like to admit it, we have to eventually migrate off this earth because it won't support continued breeding forever. It's also for the same reason that people in general, or families in particular, have to reproduce. While you might say, what's the point in caring about what happens after you're gone? Well, extinction in two hundred years is the same as extinction in twenty million.

    Unless we want to claim that human existence has no purpose or meaning, if we don't reproduce or we fail to meet the challenges of the Universe and we become extinct, then all we are, all we have and all we will ever do are as nothing.

    So many of the problems we have - mostly resource shortages - can be solved by the development of space technology. If you are like the average consumer, I would guess that 1/3 to 1/2 of everything in your house is products that did not exist before 1970, and almost all of them are based in whole or part on a direct spinoff of space technology.

    Actually, it might be arguable that the idea of working on the Gobi Desert or places of extreme cold may have uses for space exploration or vice versa. But because there are processes and capacities which are only possible in hard vacuum and no gravity, there are ways to get rich from developments in space - developments that cannot be done on earth - which means that the work in outer space could easily result in huge payoffs. But only if we have the courage to think long term.


    Charlie @ 133: Get dug in for the long slog

    IOW, take "the Space Age" seriously -- as in Iron or Stone, rather than as a modestly stretched version of the year of the LAN :) As you know perfectly well, this alienates most of the 15-to-35-year old core demographic for space enthusiasts, because it chills their fond expectation that the milestones will again start coming at that thrilling 1957-1972 pace -- whether by renewed Will and Purpose, by zoomy tech, or by entrepreneurial mojo.

    Here's my snarky taxonomy of the attitudes that need ditching:

    Fixing humans to live in a new environment is easier than changing the environment to support humans

    You can see this working itself in the evolution of Freeman Dyson's thinking. We've talked a lot over the years about the reception of Orion NPP. He's acidly funny about how many space enthusiasts enshrine it as "that great high-Isp propulsion scheme that never got a chance," while forgetting that he and Taylor came up with it precisely because they couldn't persuade themselves that chemical or even nuclear-thermal would become cheap enough to get us into space on an interesting scale or timetable. It's not happenstance that he has gradually turned to some combination of IT and engineered organisms to go in our stead.

    take a moment to ponder the political (read: anti-terrorist, not to mention anti-covert-nuclear-strike with ICBM disguised as sub-orbital bizjet) implementation headaches surrounding such a development

    Oh, you can be cruel. Every time I raise this point to the High Frontiersmen, it produces grimaces, a pained silence, and a flurry of hand-waving about how we'll have commensurate defensive systems by the time it could become an issue.

    You're absolutely right, of course: the space age was born with rapid delivery systems for small thermonuclear payloads, and they're still joined at the hip as ultima ratio regum. It takes chronic tunnel vision to believe that neither governments nor public opinion will notice this potential downside to affordable, off-the-shelf, proliferating suborbital technology.


    The only fault I can find is your assumption the humans do not care about the collective survival of the species. Some do not, even the majority, but in my opinion they should be the masters of their fate just as we must be. Political entities should also not determine mankind's eventual fate. These are the most selfish of all of us, and have a 4 year half-life. The shorter the attention span, the less likely they are to so something that requires several lifetimes to achieve. Again, let them be the masters of their fate, but beware of the power they wield.

    All of your excellent mathematical proofs and analogies are based on commonly accepted scientific knowledge right now. The magic wand you speak of will probably not be "warp drive" or similar SF plot device, but rather a way of generating kinetic energy at efficiencies not possible today. Bear in mind that today's breakthrough was yesterday's impossibility. If you could go back to Intel around 1985, what would they say about a 3GHz multithreaded, multiple CPU on a chip processor? Impossible? We can buy them at CompUSA, 20-25 years later, for around $500.00, and that price will likely drop below $100.00 in five years when we do something else that was "impossible".

    The "eggs in one basket" argument is a bit overplayed by folks who do not understand the implications. Given todays knowledge of the asteroids with a potential to strike the earth, What are the odds of getting hit on any calendar year? Pardon the pun, astronomically low. Recalculate those for a million years, and the odds begin to become worrisome. This is not fear-mongering, it is simple statistics, and I am not a betting man.

    My point? Worrying about yourself to the exclusion of all others has fettered the human from taking the next step in his evolution. We must expand to prevent the eventual extinction of our species. Before we do so, we must grow to have a long view, one which surpasses our own lifespan, and certainly surpasses a 4-8 year term to a political office that will likely not be remembered a thousand years hence.

    Just my 2 cents worth. Hope you feel better soon and kick the cold.


    Ulf Joronen


    Lessee, he can't spel wurth a dam, he can't add two plus two and even get five, and he has also admitted he has no faith in mankind's ability to overcome pretty much any obstacle it puts its mind and shoulders to.

    So why is he wasting his time writing science fiction? Seems to me he'd be more at home writing depressing songs for goth groups!


    To my mind, the primary problem is not physics, but politics.

    94 had it right, bringing back Orion would be a great start towards space colonization.

    Systems like Orion do not suffer from the high-ISP-but-thrust-measured-in-mouse-farts problems typically encountered in electrical propulsion. This is because, basically, spacecraft like Orion just detonate nuclear bombs and ride the shock wave. A system like Orion is technically achievable now, it's just bloody expensive.

    I'd also like to make a point about the thrust/efficiency trade off mentioned in the essay. Nuclear fusion propulsion, particularly pulse detonation models like Orion, are capable of interstellar travel within 'reasonable' amounts of time.

    My degrees are in astronautical engineering, and one of my graduate research projects involved doing a constant thrust trajectory analysis from the earth to jupiter using a nuclear fusion propulsion system. The trip took two weeks assuming 50% higher thrust (higher than that and the solution wouldn't converge, and I didn't have time to write a stiff equation solver).

    Antimatter has been produced for at least a decade, that may also open up new doors for us.

    Furthermore, I expect major breakthroughs in physics in our lifetime. No one can explain how gravity works or why objects have inertia now: as we learn more about how they work our fundamental assumptions about physical limitations may change as well.

    Everyone "knew" that it was impossible to exceed the speed of sound at one point in time because mathematical models demonstrated that one's drag became infinite as objects passed through Mach 1. The equation uses the same form as the Lorentz equation that mathematically 'proves' that FTL is impossible.

    Mathematical models are just that: models. They can be flawed, particularly around singularities.


    I've just lost all faith in Boing Boing. Never thought I'd ever see them promoting an obvious troll as if they were speaking rationally. Cory, Xeni and the rest really must have a talk with their drug dealers, because their happy pill supply obviously got tainted somehow.


    The author is demonstrating a typical close-mindedness, and refusing to learn from history. Think about the prospect of going to the moon in 1890. The energy source doesn't exist, the average person uses a horse for transportation, and the biology, physics and materials science is not sufficient to put a man 1 mile up in the atmosphere let along getting him to the moon and back. In fact, an overwhelming majority of Americans beleived God created the world in 6 days (well, some things haven't changed). Within the span of one human life-time, and NO failed attempts, several men walked on the moon, computer controlled spacecraft are in the process of exploring the solar system, and world-wide communication is instantaneous and commonplace. I think that constitues several "magic wands." The next 30 years have been even more amazing. Since the rate of technological advancement has accelerated incredibly since then, history shows that things we can't even imagine now will be commonplace before today's college students retire. -Chris


    I'm in the electronics industry, where Moore's law has been upheld much longer than anybody (including Moore himself) has thought would be possible. Seems that we finally are starting to see the slowing down of the process, but look at what has been achieved: billions of transistors on a chip that costs a few dollars. Don't tell me that semiconductors is the only field that such progress is possible.

    BTW, the electronics revolution is as much a revolution of economics as anything else. The increasing transistor density would mean nothing if the manufacturing processes didn't keep improving making the final product cheaper and cheaper.

    The lesson? Exponential growth cannot be kept up infintely (of course), but it can last much longer than you think possible, and the results will then be amazing.


    I believe I mostly agree with you --- certainly at our present state of technology, manned space flight is a non-starter. It's just too expensive to lift something out of our gravity well.

    That said, I think that the following is a weakness in your argument: "And I don't want to spend much time talking about the unspoken ideological underpinnings of the urge to space colonization, other than to point out that they're there, that the case for space colonization isn't usually presented as an economic enterprise so much as a quasi-religious one. 'We can't afford to keep all our eggs in one basket' isn't so much a justification as an appeal to sentimentality, for in the hypothetical case of a planet-trashing catastrophe, we (who currently inhabit the surface of the Earth) are dead anyway. The future extinction of the human species cannot affect you if you are already dead: strictly speaking, it should be of no personal concern."

    It seems to me that if an interest in the continuation of the species, society, etc. or, indeed, anything beyond one's immediate lifespan, is ruled out, than there's a lot of baby that's going to go out in the bathwater besides simply spaceflight.

    I believe that preventing global warming, easing disease and poverty in Africa, making a lasting work of art, etc., etc., all would fall to this same argument.


    I enjoyed reading the article, well said and well thought out.

    But I don't believe in it.

    If we were to believe interstellar colonization or interplanetary colonization wasn't possible we would never actually take the time to find out it was :)


    Monte Davis @171: no reply needed because you are, of course, Right.

    Ulf @172: the "eggs in one basket" calculation is not an argument for colonizing the galaxy, but for properly funding Spaceguard and having some asteroid-nudging contingency plans ready to dust off at 12 months' notice. The rest of your comments I find somewhat hard to comprehend.

    Paul @173: I come from Leeds, home of the Sisters of Mercy, cradle of Goth back in the late 70s/early 80s. Are you surprised?

    Daniel Pasco @174: the "everyone knew" model you cite for the speed of sound was clearly bogus even at that time because supersonic phenomena were observable -- propagation of lightning bolts, the crack from the head of a whip, even rifle bullets. In contrast, I don't see much evidence of non-zero-mass particles exceeding the speed of light in vacuo around us. If you know something that I don't on this subject, please speak up -- I'd love to know!

    Antimatter has indeed been produced for over a decade. Have they managed to up their production rate at CERN to more than two billion years per gram of neutral anti-hydrogen yet? I think we probably need to measure production in kilograms per year before it's going to be much use for interstellar propulsion (although for interplanetary noodling around, or mad bombers, it'd be great).

    Robert @178: I stuck in the paragraph you homed in on specifically because so many of the loudest space colonization enthusiasts appear to be American libertarians and conservatives. Yet it's an enterprise that would appear to be profoundly incompatible with their ideology. There's an interesting nexus here between American nation-building mythology and politics that I think a lot of these folks are very loath to examine.

    Oh, and finally: THE UNIVERSE DOES NOT OWE US A LIVING. There have been an estimated billion species on Earth before us. None of them have made it off the planet. 90% of them are extinct. There is NO GUARANTEE that we'll make it off the planet, or avoid extinction, either. Even if SOME humans make it off the planet or avoid extinction, we personally may not be among them. Any belief that we will or must do so is essentially teleological in nature -- it's a religious creed, not one based on evidence-based reasoning.


    We're already travelling through space, did that already occur to anybody? We just have no idea of our destination ....


    But if you want to go for a ride out of our solar system, why not use a whole moon as your spaceship?

    Europa is probably too cold and too near Jupiter, but what about titania or any other of Uranus moons? There's plenty of H2O and He3 there you can use as fuel for the whole trip.

    A fussion device that uses H2O and He3 as fuel can be useful there to provide some light (to grow veggies and chicken) and useful as well to move the moon out of its orbit into outer space. You can probably gain some gravitational impulse from Uranus.

    And then, for the whole trip, just eatch chicken, drink water and, say, play baseball.

    Finally: do you have colds often? (Thanks for this entry!).



    I'd like to play devil's advocate to your sobering analysis:

    a) Your comparison of the energy requirements of the spaceship to the total current energy output of humanity neglects to consider the historical exponential growth pattern of the latter. Your numbers may not look so bad in a 1000 years.

    b) If we consider speeds in the neighborhood 0.99c, relativistic time dilation becomes significant. At these speeds the traveler hardly ages while getting to his/her destination. In the meantime, most of the people travelers leave behind will be long dead.

    c) I say "most of the people", because it is conceivable that travelers on other 0.99c-capable spaceships can arrange to meet again at future space-time rendezvous points wherein they have each experienced roughly the same amount of time passage.

    d) And the social structures necessary to support a network of space-time-rendezvous-ing travelers may make for an interesting setting for an SF story. (For example, they would have to catch up technologically with non-traveling societies for which time has elapsed faster.)

    e) Looking further out, say 10,000 years from now, all bets are off. Our understanding of physics, our understanding of its constraints and limits, will likely be entirely different than it is today. We don't really understand QM, and we don't really understand some of old and new spooky action-at-a-distance experiments involving paired quantum particles, suggesting it might be possible to setup a telegraph line that transmits information instantly. (See, for example,

    f) All said, I'm not nearly as gloomy about space travel in the distant future (say 1000 years), as you are. But I do agree with you that there is little point in setting up colonies anywhere in space in the near future.


    Charlie, a wonderful essay, even though I thought it was missing some salient points, such as the fact that a good part of the reaction mass that you need to carry to Centauri will be gone after accelerating, i.e deceleration from 10%c towards Centauri will need less fuel than the acceleration. Or the fact that the obvious way to generate goods, structure, food, air, water etc in space would be to manufacture it there, either from asteroids and jovian moons if one wants to avoid large gravity wells, or on the surface of Mars which has all that is needed.

    As for the why, and discounting the eggs in one basket case, I would think that low gravity jogging on Mars, looking over the cliffs of the Vallis Marineris or down from Olympus Mons, owning your own asteroid, or flying in some future craft over the deep blue seas of Neptune or Uranus would be quite a powerful pull if it was fairly painless to get there and didn't cost to much.

    Added to that, I'm pretty sure that people will adapt with technology over the years to being better ablae to live in zero gravity, hard vacums and extremes of cold and heat. We might look a bit different though.


    Your comment about interstellar space exploration being an afterthought of post humans makes me think this might be true in general. For any species to be able to afford interstellar space exploration they would already need to be at a level of economic abundance to not need to do it. In that case the only people doing it would be thrill junkies specifically teenagers. Maybe that explains why all the aliens who seem to visit Earth in remote locations instead of contacting our governments are more interested in kidnapping people and anal probing them. Probably these are the alien equivalents of high schoolers driving around and mooning people in other cars.


    The first British colonies in Australia were penal colonies. The people who were sent out here (both the prisoners and their naval guards) were effectively put into exile, and told "don't come back". They were sent to a land completely alien to them - right down to the hostile biosphere, and the completely weird biological patterning (Tim Flannery has all the details in "The Future Eaters", but to cut a long story short, the Australian biosphere is a remnant of a very, very old ecosystem, and has survived mainly by being internally stable on a hair-thin balancing point). Yes, free settlers started coming out very shortly afterwards, but even in the supposedly "free" colonies (Fremantle/Swan River, Melbourne) convicts were imported to build most of the infrastructure. The Swan River group of colonies was importing convicts at a time when most of the Eastern colonies had stopped.

    It appears to have been a successful method of colonisation for an otherwise "inhospitable" (well, culturally inhospitable to the Europeans - Aboriginal Australians managed to cope with it for about 40,000 years or more) area - put people there you don't much care about, and let them make the best of it. Once they've shown people can survive there, then you let the poor and indigent head out as fast as they can. Australia is largely a nation of exiles.

    However, I'd point out that even here, the population is sparse (compared to our near neighbours) and very unevenly spread - it's concentrated in the few areas which are suitable for European-style agriculture and city development, and there are vast chunks of the country which aren't touched at all (if only because nobody has found any minerals under them yet - or possibly an economically viable way of removing any minerals which are there). It may be the case that the Australian model of exploration and settlement (a few highly concentrated areas, a slightly wider are with occasional settlement, and vast areas of nothing at all) would be one which is better suited to considerations of interplanetary exploration and settlement.

    I'm not a scientist or a physicist. If I have a background in anything, it's history and social theory. I would say that colonies elsewhere in our solar system are a likelihood, if only because humans are curious creatures, and they can put up with any amount of hardship so long as someone else is suffering it. The political and economic leaders who make the decisions about interplanetary and interstellar exploration won't be planning on joining the exodus themselves. They'll just make decisions about which other types of people should do it. After all, the US is starting to have the same problems with its prison systems now that the UK was having back in the late 1700s. I'd give it maybe another century or so, but if there hasn't been a massive alteration in either the US penal code, or the US legal system, there probably will be colony ships sent out with the contents of a couple of high security prisons.

    Either way, the point has to be made that any form of colonisation (and you can check this in history) has generally involved a certain amount of coerced, involuntary labour. In the US, it was slaves. In Australia, it was convicts. In most other countries, it was the native inhabitants (and both the US and Australian colonies had their share of enslaved natives as well) either through straight enslavement or through taking them as prisoners of war. The Vikings had thralls. The Romans used prisoners of war, as did the Alexandrian Greeks. I suspect that the involuntary labour of the interplanetary colonies is likely to be convicts, or debt-stricken bondslaves, or both.


    How about hauling an asteroid from the area between Mars and Jupiter on an Earth-orbit and processing it to raw materials?

    Theoretically, isn't directing an object closer to Sun a bit like pushing a stone downhill? Initial energy to budge the thing is big, but once rolling, the gravity will do the job.

    The aiming, of course would have to be pretty good. You wouldn't want that couple of km-diamater thing hitting earth...


    Your analysis is much appreciated and appears valid to my layman level math, but your conclusions are a stretch to me. I'd like to point out an applicable truism, What can be done, will be done. What seems impossible at this time, will be everyday in the future. We already know that nanotech based seed ships are a valid "magic wand" because we have the wildly successful biological analogues here on earth blowing in the wind, riding in guts and waiting in dirt every moment of every day.
    As Drexler pointed out long ago, nanotech assemblers require no "magic wand" breakthroughs, only standard engineering progress. AI is also necessary and clearly it's not the slam dunk they expected 40 years ago. However it doesn't matter whether true AI is invented, as long as it can be simulated in software by sufficiently powerful hardware, that will be good enough. I don't disagree with any of your facts, but after the invention and commercialization of AI and full nanotech assemblers, seed ships will be a trivial expense for rich individuals and governments. Seed ships with nanotech shouldn't care about centuries. I'm much more concerned about whether we can survive the development of full DNA designs or early nanotech assembler releases. After all, Madam Curie didn't die from old age.


    "Ah... wrong. They very much could touch us. Or have you forgotten the premise for the success of the Loonies' revolt in Heinlein's The Moon is a Harsh Mistress?"

    Damn shame Heinlein never actually did the math in that one. Given the numbers he provides, the wave that hits London at one point is around 7 cm and it should have taken about thousands of hits to excavate Cheyenne Mountain the way that they do in the book.

    Note that this had an error: I estimate the number of 2 kt hits that it would take to destroy Cheyenne at 125, when I later realized that the correct number is closer to 200,000.


    I wish I didn't agree with Charlie. I'd dearly love to see the USS Enterprise, Serenity, TARDIS etc. flying for real. But the brutal fact is that most of the suggestions for getting to the stars pretty much amount to "if we burn all of the solar system for fuel we might just get there eventually" and/or "with one bound or hero was free."

    The idea that antimatter is an answer is typical of this worldview - if make the stuff to use as fuel a lot more energy will go in than comes out. There are no magic antimatter planets anywhere nearby, as far as anyone knows, so we can't mine the stuff. Zero point energy is a laboratory phenomenon that can barely be measured, with no reason to believe it can be scaled up. Total conversion doesn't work, with any foreseeable technology, and if it did would you want it used anywhere near your planet? Wormholes are the size of subatomic particles if they can exist at all. And so forth. There are energy sources out there, just not the concentrated ones that are actually useful, in any sort of package that we can access without the sort of effort that only makes sense if the sun is about to go supernova. Which it isn't.

    It's a lovely dream, and that's why SF is fun. But seriously suggesting that it's an inevitable progression for the human race is ludicrous.


    James, I was deliberately ignoring that one on grounds of lack of reading comprehension skills. (He went from an argument about isolation due to extreme distance being undermined by communications -- "hey, mom, my ping packets are getting through, even though the latency is 5600 seconds!" -- into "The Moon is a Harsh Mistress" without even stopping to check the intersection for an oncoming "Neuromancer".

    I keep refreshing these comments expecting a chorus of line-dancing space rats to can-can on stage singing TANSTAAFL, but no joy (yet).

    I am tired, it is past 10pm, I have just won a Locus award, so I AM GOING TO THE PUB NOW TO KILL SOME BRAIN CELLS. Thank you.


    188: "What can be done, will be done."

    Ah, then since it is technically possible to build a railway from South Africa to Chile via the Bering Strait, such a line must exist and since it is possible for one or the other of the American parties to totally dominate Federal politics, both parties must simultaneously enjoy a monopoly on power.


    I generally agree with the original posting. Until we discover a solid economic reason (raw materials, food, etc.) for making the trek to the moon, Mars or even the closer star systems, it's just not worth effort and expense to send humans. However, I think that there may well be economic reasons for making the effort, but until we send more (and better equipped) robotic probes we won't know.

    Speaking of robotic probes and their technology, I believe that there is a misconception about how current space research advances technology and improves our daily lives. In the heady days of Mercury, Gemini, and eventually Apollo, there was a huge push to meet a political agenda. Meeting this agenda required the development of new technologies and techniques. As spin-offs we ended up with new materials for aerospace, compact electronics, and Tang (among other things). The Apollo project was massive in scope, audacious in its goals, and staggeringly expensive.

    Today, however, we don't have the same level of political commitment. The money to push the technological envelope the way that the Apollo program did just isn't there, and we've run up against some brick-wall physical constraints with current technology.

    For example, we're flying computer hardware on our satellites and planetary probes that is between 10 and 30 years behind the current state-of-the-art. Why? Because modern processors would die a quick death in the hard radiation environment of space and high-capacity disk drives are useless in a vacuum (they need air to operate--the magnetic head "flies" above the disk on a cushion of air). So we fly stuff that is old, slow and already proven. Granted, there may be some gleanings there from the software used to control these devices, or in novel ways of devising simple mechanisms to perform in harsh and unforgiving environments, but the real payback is mainly the science. Until we can devise hardware that is more tolerant of space we're going to hobbled, and until we push the envelope we won't get the hardware needed to really do the science and exploration I know the scientists and others would like to do. Without the political commitment to provide the necessary resources, it just isn't going to happen any time soon.

    Until we can get our technology up to the task, I believe we can forget about flying humans around for anything other than political posturing and limited rock collecting expeditions. So, wanna go to the Moon or Mars? Start writing to your politicians.


    I think the author has missed a few facts about previous human experience with large "impossible" projects.

    First, there was the building of the Pyramids. Gigantic structures that took generations to build, and which were built by people who were barely out of the stone age.

    The construction of the pyramids with only copper tools, no wheels, and with a very simplistic understanding of mathematics and engineering, by people who hadn't yet even figured out that they were living on a spherical world, makes the colonization of the moon and mars given 21st century technology look like child's play in comparison.

    Second, look at the almost "impossible" nature of the colonization of the Americas. I'm not refering to the European colonization, but to the first colonization of the Americas.

    People walked from Northern Siberia, and into Alaska, with nothing but stone tools, and the sewn animal pelts on their backs.

    Anyone who has ever been to Northern Siberia, or who has ever been to Northern Alaska, can tell you how incredibly inhospitable to human life those places are... and yet people were motivated to walk for many hundreds of miles through that area.

    And, many tens of generations later, their ancestors were living everywhere from the frozen wastes of Alaska, to the searing burning wastes of Arizona, to the humid jungles of Brazil.

    A nicely-equiped generation ship that took 400 years to reach a habitable planet around another star, would be a walk in the park compared to the 1000-year-long journey that the original discoverers of the Americas undertook.

    Heck, for that matter, there are the Polynesian peoples... who navigated the entire Pacific Ocean in boats made out of hollowed logs, and settled everywhere from Hawaii, to New Zealand, to Madagascar.

    If we (humans) can colonize the far reaches of one planet using hollowed-out logs, we can colonize the others using presurized ships. It might take a thousand years, but we've done it before under much worse conditions, and with much less technology.


    Interseting ruminations.

    There is one possibility that would allow humanity to travel at light speed without breaking any physical laws, digitized minds. I'd say that we as a species are a at least century, perhaps more, away from being able to digitize minds but the more we learn of our biology, the more we'll discover just what parts of that biology give rise to "I" and what parts are purely for body maintainence purposes.

    When we understand the "I" we can work towards creating suitable non biologic containers to house them (ie robots) From there it would, at least in theory, be possible to send "body factories" off into space and beam minds coded in em signals to fill them. This would provide an additional interesting side effect that a single "mind-copy" (say a highly trained geologist) could be sent to many different targets.

    The individual mind copies would each have their own experiences in their host bodies. When their mission on a specific world comes to an end, they could beam their minds (and all the knowlege they acquired on that world) to a network of interstellar "god nodes" which could collect the knowlege and allow the individual copies to merge with each other or or not, as they so choose.

    To be sure, this is at least a hundred years in the future and perhaps several hundred (I think we still have a great deal to learn about the components of consciousness and the physical structures required to house house it) but we're taking our first baby steps in that direction. If we don't blow ourselves up in the meantime, we will eventually learn how to do this and then, we can travel between the stars at C encoded in beams of light.


    The solution to interstellar travel, if it does not come from some "miraculous" means such as creating wormholes, teleportation or other similarly magical means, will lilely be accomplished using physics as we largely understand it today. Which isn't to say that's a bad thing, as we do know a lot of very useful things, like how much energy can really be created from matter (or antimatter) interactions.

    Even if that is the case though, our only enemy is time, not physics. Any case for travel which requires lots of energy can substitute time instead and if physics doesn't allow the creation of more energy, medical science seems more and more likely to allow the creation of more time. The human 2.0 case thus, to me, seems the most likely enabler of interstellar travel for a person in a single lifetime.

    Interestingly, there is nothing about the rate of medical progress today that would lead me to conclude that I will have no chance of living for an indeterminate and long period of time. Our exponential increases in understanding of biology, combined with advances in nanotechnology lead me to be optimistic about the things we will be able to do to ourselves in the reasonably forseeable future. So while it may remain out of reach for us to accelerate a 2000kg mercury-capsule sized object to 0.1c due to the energy requirements, it MAY not be necessary to do so as we overcome the limitations of our biology and buy ourselves time.

    The reason I find this particular solution to the problem appealing is that it still has the possibility to apply to those of us who are living right now. Even those who do not subscribe to the altruistic 'my-genes-made-me-do-it' long term planning required to create a generation-ship type craft would be able to live long enough to simply fly the ship themselves.

    Thus, we have at least two ways of cracking this nut: "magic" physics or believable advances in biotechnology (accompanied by learning how to cope with our changed biologies.) Space-colonizing Methuselahs, if you will.

    I would be interested to see a biotechnology-oriented version of Charlie's post, aimed at suggesting or discounting the idea of interstellar travel as primarily enabled by advances in medicine rather than advances in propulsion.


    Wish I could believe that humankind will reach another world in my lifetime, logic says it's going to be a long time though. If humankind reaches another system in the next thousand years, we'll be lucky. Our current space program is like trying to explore all of the world's oceans with only a canoe. Colonization on a habitable world in an alien system could be thousands of years away, if ever.


    the most aberrant thought in the essay is that the Gobi "is ugly". no wonder you can't see the future. you can't even see the now.


    194: but it took a thousand years to do it, in steps. There are no steps you can do easily in space. Moving along the coast of the Americas, you are fairly certain that where you stop for the night will be a possible home. Above 12,000 feet you have to carry oxygen in your craft.


    LOL the humans don't know everything yet. There may yet be one or two discoveries to be made that would have a bearing on this problem.

    The humans aren't out of "Eureka!" moments... I wouldn't put anything past the humans... Is there anything they like better than solving problems? :-)

    We are a "Magic Wand" making species... bah humbug all you like!

    I don't expect to see Space Colonization in my lifetime... but that doesn't mean I believe it can never happen... I think we still have plenty to learn about reality. Who knows what we will eventually learn?


    [QUOTE] properly funding Spaceguard and having some asteroid-nudging contingency plans ready to dust off at 12 months' notice. [/QUOTE]

    That's another worthwhile economy booster!

    Any huge government project, that involves space, but doesn't have a military application as its ultimate goal is worthwhile IMHO.


    Congratulations on your Locus Award! :-) Thanks for writing the original article, no matter what people feel about space colonization, articles like the original one help keep the discussion grounded in reality. :-) We will not get off the surface by waving our hands dismissively at every problem that arises! :-)


    bill @ 201 - I see where you're coming from now (actually, you said so in an earlier comment) -- given that people are going to be going crazy anyway and plunging economies into stupid projects, then the idea would be to divert that away from, say, war in the Middle East, and into, say, space.

    I like the way you think.

    bob @ 198 - hey, another poster here who hasn't the faintest clue where he is.


    As a working biologist and an optimist (wishful thinker?) about space exploration, I agree that it may be more feasible and interesting to adapt humans to their ecosystem, rather than vice versa. That is what humans originally did, before advancing technology allowed us to have air conditioning in the desert.

    If anyone is interested in reading about this issue from a biologist's viewpoint, an essay about it appears in six installments in my blog, under the title "Making Aliens". Here is the starting point: Making Aliens 1


    Re "Sun goes nova" scenarios:

    As Charlie pointed out, the sun will not turn into a supernova (it would need to be at least 8 or 10 times more massive than it is now, in which case it would have gone supernova over 4.5 billion years ago).

    It will also not produce a nova, since novas (whether we're talking about classical novas, dwarf novas, or any of the other subspecies) require a binary star system with one of the stars being a white dwarf and a very small orbital separation. If there were a white dwarf inside the orbit of Mercury, we'd have noticed it.

    At this point, I'm not sure we can categorically rule out something like a nasty flare (as in Larry Niven's classic story "Inconstant Moon"). On the other hand, the Sun has evidently failed to produce biosphere-scouring flares over the past 2 billion years or so, which suggests that it it really isn't prone to suffering such things.

    Large rocks and iceballs smacking into the Earth, on the other hand, are a very real possibillity.


    203: It's like Leo Strauss, but for people who aren't fascists! We'll use the Noble Lie to convince the ignorant, feminine masses to sink their cash into a great rationalist, technocratic, chromium project. Hehheeheehhheeh!!


    Alex @ 205: Right!


    What if superluminar travel is possible? According to Heim Theory it might be possible to travel to Mars in few hours and to nearest star in few days.

    See that article please: Here are papers from Walter Dröscher and Jochem Häuser regarding the Heim Theory:

    Here is the article about Martin Tajmar experiment with antigravity:

    So, if Heim Theory is true, then most likely humankind will reach the stars within our life span.


    209: Read this about a theory behind developing a hyperdrive engine, it's very hypothetical but all the same moving GREAT distances quickly in the future may be possible.


    Fermi's Paradox not withstanding, I think that humans DO have the potential to colonize the galaxy.. Over thousands or tens of thousands of years.

    Bottom line is that unless we destroy ourselves, we will make semi-intellegent machines that will travel slowly to nearby stars. Even at Voyager'esque speeds, we'd be there in tens of thousands of years. Then these machines using local resources replicate themselves and do the same thing.

    While not within any human time scale envisioned today, this is a very real possibility that could put intellegent devices arround almost every stable star in our galaxy in relative short order (A million years or so...nothing in the galactic time scale)

    Envision the rate of human technical growth over the past 200 years and then scale that out 1000, 10,000 or even 100,000 years. The things we make will be US.


    The colossal amounts of energy required for interplanetary and interstellar travel can really only be satisfied by a fuel with an incredibly high energy density; and currently the only technology within reach is nuclear fission.

    This is the greatest argument I can think of for not consuming the fissile material we have here on earth to power our earthbound energy needs. The main arguments against nuclear energy are waste disposal and proliferation risk, both of which disappear if we send up a fertile fuel instead of a fissile one and allow them to breed their own Uranium or Plutonium in space. No one cares if you leak radioactive waste in space; maybe it could even be used as a propellant.

    Transportation on this planet only exploded once we discovered a compact and efficient fuel and invented the internal combustion engine. We've already discovered the next compact and efficient fuel; transportation between planets will explode once we have an internal fission engine. Assuming that we agree on the importance of attempting space exploration and colonisation, we need to save our nuclear material to use as fuel for these future missions, even though most if not all of them will probably fail.


    Well, while the outlook seems to be quite gloomy, I'd like to introduce another metaphor. Let's just suppose, we had no planes and no ships/boats. If we wanted to go to from Europe to the USA, we would have to swim a very large distance, like thousands of kilometers. This would also seem very impossible to us ;)


    That link I posted is the same as 207's reference to new scientist. Got the idea at the same time :D.


    Another thing I suggest is that we learn how to colonize the very deep sea trenches, since they support the same life.

    I'd rather see money put into exploring the life we know is out there, than looking for life anywhere else.


    Speed of sound varies with temperature and atmospheric composition. Mars is much colder and its atmosphere is primarily carbon dioxide. So I thought your mach 0.5 dust storms might be a bit overdramatic.

    Using your mach 0.5 number and:

    suggests martian dust storm winds of 439.2 km/h Mach 0.5 at Earth temperatures is 617 km/h. A difference of 178 km/h seems significant, but given a "very strong" hurricane can have 248 km/h winds, I think your point is still valid.

    (I got hurricane wind speeds from this page: )


    210: I was just thinking of that. It's actually a really good argument against nuclear power.


    EXCELLENT article.

    My suspicion is that you know much more than this than I do, but your article was focused on why, scientifically, space colonization is not a way to circumvent the finiteness of earth's ecology as a place that can support humans.

    My own experience with people wanting to colonize space, and more specifically the Mars Society, is that all the "Why Mars?" talk is not bad science...

    ...It's bad religion.

    As a theology student with a first master's in math, I am quite fond of Mary Midgley's Science as Salvation: A Modern Myth and Its Meaning. The book is highly accessible, inviting, and beautifully iconoclastic.

    You might like to refer to it in explaining why people think mass colonozation of space is a good way to circumvent the difficult limitations of living on earth...


    200 comments in, it's fascinating to see how many people aren't pitching in beyond 'you just don't understand'. Or are just ignoring the maths and going with the gung-ho: yes, a few of us did go to the moon, but the whole base metals into gold thing is still proving intractable, I notice...

    My worry now is that even if a deus ex machina shows up, if the responses here remotely reflect what we'll become, any interstellar travel will be doomed to tragedy, as people stop to look at the pretty rings, confident that A Way Will Be Found to make up for lost time and energy.


    Charlie, Actually there have been a lot of strange observations involving the speed of light, but no smoking guns to my knowledge.

    I have always liked the speed of sound example because it illustrates the danger of blind faith in mathematical models. Also, bullets are faster than the speed of sound, but whips are not; the crack is caused by a series of compression waves and not from the tip going super sonic.

    I'm do NOT expect to see commercial production of antimatter any time soon. Honestly, I was so astounded when it was first produced that I like to just point it out: 'hey, people have figured out how to MAKE antimatter.' It's a long way from a space propulsion system, but ENIAC was a long way from the Mac Book Pro I'm typing this comment on, too.

    Given that no one can adequately explain gravitation or inertia yet, I think it is too soon to close the book on space travel. I wouldn't believe in the ability to fold space, but I also would have a really hard time believing in gravity if I didn't live with it every day; it's one of the most improbable things I've ever heard of.

    Bottom line: what we know and can do changes over time, and that gives me a lot of hope. I personally think it's going to take a profound change in our picture of how the universe works to develop practical interstellar travel.


    Charlie (not sure who wrote this, since it's my first visit here through /.) You are absolutely right, and utterly wrong. I will not discuss any of the techical aspects of your article (I understand most of them, but just barely), because you seem to be pretty much right. However... I do understand History and Mankind. I don't quite recall the quote, but it goes something like "We don't know how the future is going to be, but it will be completely different from what we expect.". You are applying 21st century calculations to future problems. That's like a scientist in the middle ages (that's an odd bird!) trying to do the math for moon travel. You know, before Galileo, Newton, Einstein, Von Braun.

    So, either this article applies only to the near future (1-5 centuries), or you are way out of your league (no disrespect). You can't just say that things are impossible on the light of your culture. You might be an enlightened person for the 21st century, but you don't have a clue of what's possible in the 5th millenium. Just as Archimedes had no clue of what were atoms, friction, black holes, quasars, HTML, spandex, liposuctions, AK47s, cell phones, TNT, jets, internal combustion engines, gravity, Pluto (not the God, he knew that one), dinossaurs, brazilian waxes (he didn't know whole continents, let alone some form of hair removal named after an unknown country) LCD screens, helicopters, Casio watches, and so on. Aren't all these Magic Wands in Archimedes eyes? He was a complete ignorant, albeit being one of the greatest geniuses of all time. So, an ignorant as he was, he had no idea of how to go about communicating his ideas to other people on the other side of the world. I can do more than he ever could. I can post this to you, on other continents. I can phone a scientist thousands of miles away. I can fly. I can calculate the rate of descent of a falling object, and it's speed at any time during the fall. I can say how fast and hard it hits the ground, before it is ever launched. I can roughly imagine what must be needed for a travel to Mars. In a realistic way. With sound scientifical evidence and calculations backing me up. I am no genius, but I am oh so much cultered than he ever was. I am capable of foreseeing so much more things.

    And I am capable of foreseeing that Mankind will learn more than what it knows now. There will be more Magic Wands. Sure, we will never get some things. Some will be impossible. I mean defineletly and universaly impossible. But we don't know which. Maybe there will be FTL. Maybe there will be an EVENT. Maybe there will be "something" that will blow our great-grandsons' minds when they are old. And their grandsons will say "Come on, granpa, hop on, it's perfectly safe!". How can we say otherwise? How many times must we be proved wrong on the "impossibles" of life?


    Sorry for my bad english.

    Once one guy made a question to Galileu, after looking the moon in the telescope, if the man will ever reach the moon one day. Galileu saids, of course not.

    Ok, but in 1969 one man put's feet in the moon.

    Why galileu thougth that? Maybe because he didn't know engines, and others things that was discovered after him.

    So i say, for us the distances and forces looks so big that must be impossible. But like Galileu whe don't know the nexts discoverys of the man.

    And maybe one of thouses will solve the problems in a way that we cannot understand now.


    I shall enter a few threads I haven't seen touched on yet.

    To the "We've done amazing things before, therefore anything is possibe" crowd, that reminds me of the different traps involved in discussing "shades of very large". The quantity of integers is large. The quantity of real numbers is much larger.

    The point about the difference between vacation and colony is a good one. When people put themselves into "vacation-mindset", they expect to spend a proportionally large amount of resources on some experience in some attempt to garner an intangible emotional benefit that "will get them through the next three years of the grind at work". We did that with the Moon, and we will do it again on Mars. The trouble with colonies is that they require continuous incentive to continue to bother.

    Forgetting even the Deserts, I find it extremely prophetic that we can't even maintain economic critical mass in certain States of the US because it's "just not worth it". I can't fathom the costs of an unfinished attempt that could bankrupt the planet in the effort.

    Also, no one seems to be addressing the social side. Concurrent with all this "look how wonderful progress is" theme, is an increase in Communication Transactions Per Person Per Day. I think social stability is linked to quantities of communications. I am not sure we will even last 500 more years as a species, which is too short a time to even begin to properly do more than log a few vacations.


    You know you live in interesting times when you can no longer tell the difference between UFO cultists and real science.

    New Scientist article @ 207 "[Heim]claimed it is possible to convert electromagnetic energy into gravitational and back again, and speculated that a rotating magnetic field could reduce the influence of gravity on a spacecraft enough for it to take off."


    @133: "(Are we gagging yet?)"

    Not in the slightest. Meanwhile, same post: I suspect a covert reason for the delay in non-ballistic-missile-based space access was to arrest and surpress the Cold War space arms race.

    @136: "I really dont see why our robotic emissaries cant precede us and prepare an environment suitable for us."

    That's pretty much what I expect.

    Next note: I'm actually glad it will take centuries and multiple intermediate steps to build up to the power levels needed for interstellar flight. I don't want those power levels within a million miles of the Earth, thanks.

    Finally: whether most people are utilitarian or not; whether they are ideologically consistent or not; whether most people care or not -- long term plans, if not fatally flawed or mutated, outlive short term plans. Call it temporal memetic Darwinism. Eventually successful long term plans will be developed; they will succeed, end of story.


    Anyone who keeps up on these issues is fully aware of everything said here, more or less. However, it would be more productive to ask "how can we do it" than to expound upon why we cannot. The last estimate I read for a space elevator was $15 billion. Research into inflatable space habitation modules is in its advanced stages. A recent scramjet flew 330 miles up (low-earth orbit). Ion propulsion moves cheaply at 63,000mph. Mars has plenty of water and caves to build human dwellings. Mars is rich in iron, brighter sunlight than earth, and has only 38% of earth's gravity. I would suggest a settlement to harvest the iron and light-water into materials and products to send into space... that is, to build large space craft... solar system cruisers.

    If I were president, I would have purchased the Mir, tied it to the shuttle with a large space-chain and drug that the moon or Mars. Our highly advanced monkey brains are designed to solve problems, not just identify them.



    Charlie, #29. " of cultural data..." What about ecological and biological data? As a friend keeps reminding me, more data can be transmitted by a physical object than any transmission technology we now have, and physical media keeps outstripping telecomm. Which means that, perhaps, information is an economic basis for interstellar trade and John Campbell (by way of James Blish) got there first. Interesting how Blish keeps coming back to me in this discussion. Other authors who keep coming to mind of are Tiptree, Pamela Sargent, and one of Damon Knight's stories.


    [Back from pub]

    If Heim pans out as actually having anything worth following up (hint: "lone gun working in isolation" isn't usually how progress is made in theoretical physics these days) then indeed, things are going to take an interesting turn. Ditto if we come up with a model for how gravity and inertia work that allows us to do cool stuff like generate [anti-]gravity using EM sources.

    ... But again, this is magic wand territory. If you change the constraints, the results of the experiment will of course change. I'm trying to do strict extrapolation from what we currently know, here, and I'm just not seeing the love.

    (And I'd caution against taking anything you read in New Scientist too seriously. They've got a weekly production schedule to meet, and they can't afford to be too fussy about where they get their inputs from -- although this thread is giving me a lot of sympathy for their letters editor!)

    Incidentally, social issues are precisely why I picked 200 passengers as a sensible load for a generation ship; it's roughly the standard size of a primate troupe in the wild, or a human extended family plus friends. TaoPhoenix hit something interesting with that comment about communication transactions -- remember, a starship is going to be a long way from the neighbours, too far away for any semblance of real time interaction. So you need to take your society with you.

    As an aside, I'm kind of amused to see recent visitors here lecturing me about mind uploading, virtual realities, and the Fermi paradox. I'm way ahead of you guys: consider this a cold reality check on my own more optimistic projections in, for example, Accelerando.


    I admit I haven't yet read all of the comments as yet, but I haven't noted anyone discussing the huge difficulties of building a space elevetor. Geosynchronous orbit is 35,786 km (according to This means that you would probably have to either build a building this tall (bear in mind this is approximately 5.5 times the radius of the earth) or start at this point and build in both directions. Most likely both would need to be done. So, not only would you need to build a cable over 35,000 kms long that could hold it's own weight (no current material could even get close), but you would then have to arrange for a counter weight on the other end to hold the whole thing up. Under the assumption that you are using the estimate of $2000/kg to get material into space and the fact that you will need an enormous counter weight as well as the weight of the device itself, the calculation doesn't look good. Certainly, I doubt this could be done for a number that didn't run into the hundreds of billions of dollars, even if we had a material that could hold it's own weight under these circumstances. On a personal note: I grew up read SciFi and I am still a believer, but a wise man chooses battles he can win. There are huge numbers involved in these calculations, but science has conquered huge mountains before. All that this essay shows is the true value of pure research. Due to the path it has chosen to tread, if humanity is going to survive it needs to go forward: science is the only vehicle that can take it there.


    Charlie, Just want to say I have thoroughly enjoyed everything you have written (still looking for that Ninja story-just joking!).

    I think a lot of us agree interstellar colonization is way beyond current technology and in this stellar system the best real estate seems to be Mars (Luna just doesn't seem to have much in the way of useful resources, unless there really is polar ice, tritium 3 etc.). And I agree the sensible thing is to do what we can with unmanned exploration. But I want to point out NASA hasn't done a life detection experiment in over 30 years, on Mars or elsewhere. In fact, we haven't even been able to get them to fly an automated microscope of more than 4X mag(great for geologists, not so much for biologists). Things are turning around now due to discovery of great amounts of water ice, atmospheric methane etc. on Mars. Still, a human biologist would probably have a much better chance of success in collecting soil samples from the relatively UV-protected environs we really want to examine (deep in Valles Marineris, caldera of Mons Olympus, even deep sub-surface soil). Culturing the soil samples, seeing if you can grow any bugs etc. is best done on Mars due to Planetary Protection concerns here. Sample return missions continue to be controversial for that reason.

    What I'm saying is that there is an incredibly strong reason for humans to visit Mars (not colonize it!). It is simply that discovery of an extraterrestrial example of biology would be the biggest advance in the life sciences since the work of Watson and Crick! And I'm dubious that we will be able to do this with remote instrumentation. The history of the Viking experiments attests to the problems of interpretation of remotely-gathered data.

    So I'm saying curiosity may in the end be the best justification for sending humans to Mars (not necessarily keeping them there!). And human observers still trump the best remotely operated instrumentation we have, at least in difficult environments. Myself, I'd sign up in a New York minute if they were taking aging myopic biologists for a Mars expedition at this point in time!


    The naive hubris of those who say "We can and will" is only exceeded, in my opinion, by the hubris of those highly intelligent folks explaining why "We can't and won't".

    The singularity is coming! cya :)


    Its odd that you put so much emphasis on traveling in the human lifetime, and future technology, but don't mention cryogenics. You talk about the difficulties in multi-generational ships and maintaining human groups over centuries, and I agree that would be bad.

    But whats so wrong with freezing 1000 people for 1000 years and getting them somewhere. Not to mention giving them say, a 10,000 humanoid robot workforce to build a colony when we get somewhere?

    You seem to think this is impossible because its "hard" or "expensive." Thinking like that certainly didn't get us to the moon, and it won't get us to Mars.



    We will colonize the Galaxy by sending all the information required to reconstruct human consciousness to the candidate planet. All our current efforts are bent on the single task of replicating that which make us self aware; A.I


    Ok, folks, follow me on this one.

    Earth has been here about 5 billion years. We have been here (H. Sapiens) about 30,000 years. If colonizing space were even remotely possible, and intelligent life were even extremely rare in the galaxy, then someone would have happened upon our little blue marble WELL before we came along. Do you suppose they would have allowed, purposely or by accident, for our eventual evolution to progress? Not likely. Since we exist, either interstellar space colonization is impossible, and/or alien intelligence does not exist anywhere else in the galaxy, and probably not anywhere in the universe.

    In short, we are it bub. If interstellar colonization is somehow possible, then I expect there is one big, empty universe waiting for us.

    Pass me the magic wand...



    You're forgetting one thing that answers all those problems: the dreamers. Think that's a crappy statement, something vague, impractical, and kind of unfair for me to just posit as an answer? Let's think big, afterall, that's what dreamers do . . . . I would say one of the most consistent phenomenons in history is someone not being able to imagine of something being possible, or imagining of it at all, or a large group of people thinking it actually impossible, and yet then having someone go and do it. I would probably label most every breakthrough as one of those. To uncharitably rephrase your above essay, it seems in a way you're predicting that breakthroughs are going to stop happening . . . .

    One of the few things that show no sign of abating in humans anytime soon is our ability to both conceive of limits in ourselves that don't exist, and to break ones outside of us that do.

    Good luck with your writing.



    I just finished reading accellerando - which was simply the best, most mind blowing book I've read since Snow Crash. You got so many details right... (it's a shame I never met you at SCO)...

    ... 'cept one niggling detail, and you missed it in this essay, too. There are stepping stones to the solar system, better than mars, better than than the moon - the near earth asteroids.

    Delta-V to many NEAs is less than Mars, (well over 500 as of this writing - see, landing is a piece of cake, and returning requires much, much less delta-v than mars. As these orbits are elliptical (sometimes in the extreme!), many, many other opportunities exist for alternate destinations.

    Probably the most coherent thing I've written on this topic is at:

    Once you get there... (see the hera and quixote missions as examples) raw materials and radiation shielding are to be had to bootstrap the rest of solar exploration.

    but, yes, overall I agree with you that only posthuman devices will be exploring these worlds, or severely modified humans. What good are legs on an asteroid? They will be amputated at birth, as a dangerous appendage, like a veriform appendix.


    Well, I watch a lot of Stargate SG-1, so my mindset has been forever corrupted in terms of reality, but here's my two cents.

    It is, in my opinion, inevitable that science will progress further on. As we go, we'll find out that many "truths" of this age are actually false. (reminds me of an episode of SG-1, where the comment is presented that quantum physics is taught in "fallacies of primitive physics" on other planets)

    For example, going WAY back to the start of this comment festival, you mentioned the relativistic travel restrictions in terms of energy requirements and so forth. Now, I know this holds true for the current day, but to me, it is entirely probable (in fact, almost guaranteed) that one day, some form of technology will come by that will completely erase this restriction.

    I'm far, far too much of a hopeless romantic to be of any use in a scientific debate, but I like to think that technology will advance exponentially, and that certain key advances will be made that will allow for such previously unthinkable things.

    As I see it, as close as 100 years ago, we were still confined to this planet. Space travel was entirely unheard of, as were computers, personal cars, and many other luxuries we now have today. Showing my romantic streak, I like to think that in another hundred years (I hope I'll be alive to see it, although I kind of doubt it) we'll be doing things that we currently believe impossible - such as colonizing space, faster-than-light travel, and even world peace. (had to stick that one in there for my hippie slant)

    By the way, I'm probably terrible at any scientific aspect of this comment - I can say with certainty that the youth of today are far too uneducated in terms of physics. Firsthand experience. Although, your posts have started to make me consider astrophysics as a major in college again...(it's probably a black hole for job placement, though)

    Love your posts, keep up the work. I'll be reading. Probably not posting (takes too much effort), but reading nonetheless.


    For those just joining, here is a summary of many of the previous comments. Be careful! What you're about to say might have been said already.

    "I don't know who you are, Mr. So-called Science Fiction writer, but you are a pessimist! You of all people should be pushing fantasy, not poo-poo headedness!"

    "I did not read your article, but you are wrong!"

    "How can you not understand that humanity will inevitably invent magic ponies, which will carry us to the stars on their backs?!"

    "Why are you so narrow-minded, Mister Physics and Numbers?! Leave the equations out of space travel: they don't belong there!"

    Thank you, and good night.


    Q: Would a space elevator be something you could set up from space?

    ie, could we carry the makings of a space elevator with us to Mars, or the moon, and set one up from orbit?

    That'd certainly make it a lot easier to get back up into space.


    Charlie writes: "The species survival utility you mention is an interesting one, but as I've noted, it's not a clear economic benefit to us, here on Earth, to know that humans on another planet or space colony will survive even if we're clobbered by a wandering comet. "

    Seems like it's just a form of estate planning.


    Charlie, I appreciate the article and you bring home some important points very... pointedly. I do have three critiques:

  • I think you give lip service to past innovations yet maintain an attitude similar to past nay-sayers. You accuse others of having too much faith in future science. Well, I accuse you of having too much faith in current science. In 100 years most of today's scientific theories will have been falsified, or reduced, or eliminated or whatever progression theory you subscribe to.

  • You seem to lack motivation to preserve the species beyond your own person. That doesn't bother me, but as a result you seem willing to deny that such a motivation exists in other people, no matter how many people tell you otherwise. You don't have to understand it, but know that you are wrong.

  • Libertarians come in as many flavors as there are libertarians. Like many people, you appear to write them all off as a bunch of selfish oafs always in search of an impossible utopia. Here's an alternative way to look at them: they are simply different than you, they are vastly outnumbered, and your way of life precludes theirs. Like many persecuted groups in the past, they are intrigued by the possibility of having somewhere to go. Space is a hardship, but it is also a long way away from their oppressors. Just like America a few hundred years ago. Incidentally, the closest thing to a common denominator among deontological libertarians is the Zero Aggression Principle. The key to understanding these libertarians is understanding that they are not consequentialists, and understanding what that means. Their first concern is not that they have enough food to eat, or that their children can read, or that they have health insurance, but that no one is assaulting or defrauding anyone else. Once that is accepted as a policy, they say, then certainly let's get together and try to make the world a better place. They are in a bit of a pickle, since every modern state begins the task of "making the world a better place" by threatening force against its minorities in the name of its majorities. Or worse, some still do it vice versa.

  • 241:

    Wow. Lots of pissed off handwavers in this crowd. Charlie laid out a concise, well presented argument based on solid science. It's amazing to see how few of the offended have managed to string together a remotely rational, fact-based argument in response. This more than anything else tells me we aren't colonizing the solar system, let alone the planets, anytime soon. Wishing upon a star ain't gonna get you there.

    I think the Fermi Paradox puts a great big nail in the coffin of interstellar civilization. Given the age of the Milky Way, we should have been visited and colonized by the representatives of at least one alien civilization by now. The fact we haven't tells us that either:

    1) Interstellar colonization is technically impractical or impossible, regardless of your advancement 2) Interstellar colonization is possible and perhaps even practical, but nobody with the ability to do it bothers because there are better ways to spend your time and energy once you have technology that advanced 3) Civilizations never acquire the ability to colonize the stars because they're wiped out by their advanced technology, via wars, accidents, runaway AI or other processes

    There are other possibilities as well (like interstellar exterminators, who go around snuffing out technological civilizations to prevent them from spreading), but they all seem far less likely.

    I'm betting on option 2, but 1 and 3 wouldn't surprise me.


    Catfish N. Cod @ 224: ("Eventually successful long term plans will be developed; they will succeed, end of story.")

    Funny, I just got back from Baghdad and that was the official line there, too.



    Thanks for a thought-provoking article! I won't argue the math. You're right, it's a Big Problem. I still find myself hopeful, though, because I suspect it's also an Essential Problem to the long term survivability of our species.

    But you mentioned some sociological issues. I will point out that I myself spent ~13 years living in tiny villages of Kaktovik and Atqasuk in Alaska. Note the populations, the latitudes, the weather. During my time there, I was once asked to sit as a panelist at a science fiction convention. The topic was basically 'life in space' and I'd been asked because I lived in such an isolated community. Of course I couldn't actually justify the trip - transporation costs were exorbitant.

    Residents of these and other Arctic villages don't rotate in and out - they make their homes there. Yes it's an anomaly, yes there are some unique economic factors propping up these villages, and yes, the isolation factor is at least an order of magnitude lower than you'd have on an interstellar voyage. We did (usually!) get weekly plane-loads of goods from the Rest of The World.

    But small communities can survive in pretty deep isolation. During my first few years there, we had no television linkup to the RoTW, and one phone in the center of town. Newspapers were rare and basically irrelevant.

    So, I'll posit that this really is an energy problem, and a closed-loop ecosphere problem. I think the sociological problem you suggested is much immediately approachable than you seemed to suggest.


    I've loved SF all my life but I have no problem acknowledging that Charlie is entirely correct here.

    No matter how many things that would once have fit the description of 'magic wand' have become common place, there is no assurance that a desired technology will appear. Ever. Just because you want it badly doesn't make it doable. Nor does the ability of SF writer to envision the miracle tech in everyday use bring it any closer to reality. Otherwise we'd have already have colonized a few hundred world with super-intelligent robot dogs protecting us from the local bitey/clawy things.

    The past is not a predictor of the future. Yes, we went from Kitty Hawk to Apollo within a human lifetime but speaking as someone who was born around the time of the first humans reaching orbits for a few scant minutes, we've progressed very damned little in my 43 years. This isn't just lack of political will. The objectives simply aren't demonstrably worth the cost for anyone who isn't an enthusiast and we're very much in the minority.

    Enthusiasm isn't enough. The Kitty Hawk to Apollo pace of advancement may seem remarkable but we've had enough time to gain some perspective and realize that doing those things were easy. It was only towards the end that it became an enterprise requiring the resource of the planet's wealthiest nation. The in-atmosphere stuff got some boost from wartime R&D push but most of it was accomplished by tinkerers and private enterprise was a clear cut business potential. Much as we'd prefer otherwise, manned space access doesn't have a clear market beyond the ultra wealthy. Commercial air flight became accessible to the middle almost immediately upon its commencement.

    As Charlie detailed, it's a matter of scale. Columbus wasn't doing anything that extraordinary by the measure of commercial shipping industry of his day. It wasn't a matter of if but rather when. Ships didn't need all that much improvement to make voyages between Europe and the New World a thriving business, once it was known there was a place worth spending all that time at sea to reach. If Columbus needed a century or more to report back his findings, how interested would any potential investor have been in backing his venture?

    Seriously, this stuff is really hard and there is no guarantee that a mitigating technology will come along. That doesn't mean we should stop hoping and dreaming but it does mean any Hard SF writer worth reading has to understand these issues. But remember the physics and math needed to get to the Moon were well understood a lifetime before Apollo. The same can be said of the math and physics needed to plan interstellar travel but we are scarcely any closer to actually doing than we were in July of 1969.

    Several peopele commenting seem to believe the space program is some cornucopia of new technologies benefitting humanity. Bollocks. Very little attributed to the space program actually originated there or needed NASA's prompting to be developed. Wars, including the Cold War have contributed far, far more to the development of technologies that found civilian applications. Tang, for instance, was not developed for NASA. It was developed at the behest of the Pentagon during WWII but not delivered in time to be used. It was used by the military thereafter but got a big ad campaign after NASA's use retroactively made it a Space Age product that could be pitched to the unsuspecting public.

    Nor can NASA be credited with stimulating semiconductor technology. The money helped but there was far more money coming from the need to miniaturize guidance systems for missiles, and this started well before NASA was created. Plus there were far more nuclear missiles to equip than space launches. Before the creation of the integrated circuit RCA had mad great strides in packing components into a brick-like modular unit that was pretty nifty for the era. Further, the market potential for electronic calculator for business was vastly more than sufficient to drive the development of the microprocessor. Remember, the original Intel 4004 was developed for a electronic calculator and repurposed as the basis of programmable computers only after Intel failed to win the bid. The desires of CPAs drove the development of the microprocessor much more than the desires of astrophysicists.


    Ah, New Scientist. I don't know what I loved more, the conservation of momentum violating space drive:

    or the puddles on Mars that are on the face of a cliff:

    The hermitlike German physicist whose theories Will! Give! Man! And the Cuter Women! The! Stars! is just part of their sensationalist tendencies. The National Enquirer is about as trustworthy.

    One of the things I love about Heim theory is how its so complex, even its fans don't understand it. This led to a situation where they were terribly impressed by how Heim Theory predicted the masses of the elementary particles:

    Heim theory is fun to play what if with but it also has all the earmarks of crackpot science.


    "So Proxima Centauri, at 267,000 AU, is just under two and a third kilometres, or two miles (in old money) away from us."

    Hell. I can walk that.



    Re 111:

    Because at present there is no compelling reason to send people into space save for research purposes, the reasons people come up with for going into space reflect whatever they are most worried about. For Cole and COx (writing after the Cuban Missile Crisis) it was the need to increase the human range so that nuclear war wasn't a species ending calamity. For O'Neill, a Catholic writing after the Club of Rome crap, it was a place where bottlenecks on population could be eased. For some people now, space is where Ay-rabs and Liberals can be avoided.


    OK, I'll grant you all your caveats regarding the ability of individual humans to travel interstellar distances. But that's not the only way to skin this cat.

    We will, more than likely, survive as a technological species long enough to develop transportation technology sufficient to deliver payloads to other star systems with human lifetimes not being a limiting factor. Human beings won't be involved at all beyond the launching of such robotic star-farers.

    We will, more than likely, develop robotic technologies and AI's of sufficient capabilities to be able to code up from stored DNA patterns, human beings and an ecosystem suitable to support human existence. Even to be able to raise infants to adulthood, educating them in whatever culture and societal norms were deemed useful.

    That seems to me to make it entirely possible for human beings to spread throughout the galaxy -- in the fullness of time, even while the stock they originally came from goes extinct. And it may even be possible (I'm out of my depth here) to use coupled quantum interactions to provide instantaneous communication between scattered outposts of humanity.

    The only really difficult part is for technological humanity to survive the growing capabilities of the species while retaining most of our behaviors and instincts from our primitive past -- once every bunch of thugs on the planet has nuclear weapons (or worse), it's going to be extremely difficult for technological humanity to survive. THAT is the real challenge ahead of us.


    Antimatter catalyzed nuclear pulse propulsion


    Interesting post, Charlie. I sometimes wonder what my ancestors were thinking when they left the temperate shores of England for Manitoba, Canada. Ye gods! Winters lasting 6 months with bouts of -50C, snowbanks above doors, and in the summer, +40C, flash floods, tornadoes, boggy wetlands with killer mosquitoes and blackflies. Many of the first settlers died of starvation and exposure, not having figured out how to live in such an inhospitable climate. I agree that given current technology, it doesn't yet make sense to colonize Mars or the Moon or go anywhere of any appreciable distance, but it might make sense to people in the future with different technology and different views of themselves and the universe. I hold out hope because the number of mass extinctions on Earth in the past does not bode well for our long-term survival as a species unless we do spread out.


    Justin @ 237:



    It's all a matter of when, not if or how. Why? Because of Einstein's favourite phenomenon: compound interest, converted in this case to exponentially falling unit costs.

    Estimate a present day cost of doing interstellar travel. Estimate a long run rate of productivity growth (the inverse of unit cost decrease) say 1% p.a. Then use the rule of 72 to estimate a cost halving time (in this case 72 yrs). Keep on halving the costs until they come down to something reasonable. Count the number of halvings and multiply by the halving time and you have your answer.

    It is likely to be a conservative one. There is no shortage of matter or energy in the universe which nobody else seems to be using. Kurzweil makes a reasonable case that productivity growth rates will accelerate in future. The only physical constraint likely to cause a diminishing returns effect is if the speed of light proves to be unbreachable.

    This otimistic economics of space flight mkes the Fermi Paradox- why isn't someone else here?- even more puzzling. But then somebody has to be first.


    "Lack of imagination is often mistaken for impossibility. A fool will claim he can tell them apart, proclaiming he neither has a smart answer, yet that nobody can possibly be smarter than him. A wise man will always assume the former." -- Me

    What you basically did was try to force todays paradigms on a bigger problem. Kind of saying nobody will ever have petabytes on a PC because harddrives are only 1TB big. Which is not far from proclaiming 640KB is enough for everybody, simply because your imagination doesn't extend as far as the applications.

    Energy sources available to us are VAST and can easily provide for the requirements you've mentioned. If we started tapping thorium as a nuclear fuel, we'd have enough to sustain the current level of humanity's power consumption for over 1000 years. Producing it would simply require some specialized high-capacity reactors that run for .. umm.. a tad more than several days .

    To pull of a jump like that the bigger problem would be STORING the energy rather than producing it. That too can in theory be done using antimatter, albeit at a prohibitive cost using today's technology (somewhere in the trillions USD per gram produced) and let's not mention efficiency.

    Another thought trap you seem to be falling into is that dictated by existing paradigms that have to do with space access. If we were to ship something the size of (or 100 times the size of) the Queen Elizabeth II to the nearest inhabitable solar system, that would allow you to lose a few of those magic wands you comissioned for self-replicating stuff.

    This may yet happen well within in our lifetime, if CNT's get developed to a point strong enough, weavable enough and cheap enough to allow us to build space elevators. If that happens, there's absolutely nothing that prevents you from reasonably getting as much tonnage into space as you like with some very wide margins for "reasonable"

    Another hidden assumption you're making is that human lifespan (more importantly, the healthspan, no use getting disabled and deteriorated old people who can't controll their bladder to another system) will remain as it is. Another paradigm-shift may be awayting us around the corner in that field as well. check out (they're not selling anything, other than scientific roadmaps). A human 100 years old in a body wear-and-tear-wise equivalent to a 30-year-old today can change some key parameters in your equation. And it may very well happen sooner than later. In fact, using your magic wand numbers, he may have already completed a two-way trip.

    Your article basically comes down to "The impossibility of going to other solar systems TODAY". Way to go, Sherlock. All I see you can do is recite 50-year-old sci-fi paradigms, not apply imagination to what different direction things may start developing tomorrow.


    What about terra-forming Mars or the moon to make it hospitable?

    I think you forgot that one =P


    238: Yes. An elevator can be spooled down from space. That is how you deoploy the initial seed cable when you build the first one, and that is how you deploy a full SE if you have the means to raise it up to space (using, say, another elevator, or when you come to deploy one on Mars). This makes for what is a very intriguing hypothesis, that whoever builds the first SE will own space, simply because the exponential rate with which he can replicate his elevators will keep him owning much more than the competition.

    In fact, since SE's would provide more than just a way to leave the atmosphere, providing also a means to slingshot yourself between planets, the FIRST thing that would be reasonable to set up on a mars colony is a SE that can slingshot things back to Earth.

    And unlike for Earth, the materials required to build a martian one already exist.


    Magic wands are a dime a dozen!

    Seriously, its pretty easy to think of 100 things today that would seem like a magic wand to people only a 100 or even 50 years ago. Why are you so pessimistic about future technology, you have absolutely no idea what will be invented in the next 100 or even 20 years.

    Of course colonizing the galaxy with todays technology is absolutely absurd, its like calculating how much steam engine energy it would take for you to get to the moon, theres no way you can build a locomotive big enough to get us there! and it weighs too much made out of iron!

    I believe we will have advanced AI go to mars and beyond way before humans will, humans will make it to mars about the same time child like AI is coming out (10-20 years) I would think, who knows, no one does, but it will happen eventually, and yes even space colonization, its innevitable, 100 centuries from now, 1 million, who knows, how can it not happen?

    People will go because of curiosity and adventure, the same reason they climb everest.

    It was an awesome article, it got me thinking and I like that, thanks :)


    Carrot @244: "Funny, I just got back from Baghdad and that was the official line there, too."

    It's true, too. It doesn't mean it won't hurt, or be unpleasant, and it doesn't mean that the people who start will be the people who succeed.

    Iraq will not in chaos forever, and we will not be stuck on Earth forever. It also won't happen on ideologues' timetables, or look like their initial dreams. Which is Charles' point.

    My point, on the other hand, is that his vision is self-limited to his own projected lifetime; the picture changes as you look further in time.


    Re 256:

    As I recall, Martin Fogg got a timescale to terraform Mars of a few thousand years. Humans suck at deliberate programs of that length.

    You'd have to import a crapload of volatiles to terraform the moon, since it is bone dry. It's probably easier to work out some way to melt Ceres and commit ecopoesis on its world-sea (You'll need a plastic sack to keep the air from escaping).

    I reserve the right to feast on the tasty brainz of the first person to propose terraforming Venus with a handful of algae or who thinks moving Ceres would be easy because it's not in a gravity well.


    Kelvar is good enough for a lunar beanstalk.


    At our current level of our technology, this blog holds true. Space travel in this point in our evolution is absurd.

    You are forgetting though that there may be other forms of travel through the universe besides basic point to point explosive sub light speed propulsion. Physics that is still on the drawing board in the next Stephen Hawkins basement may be the basis for it. Its just too bad that many of us may not be around to see it.


    Its just too bad that many of us may not be around to see it.

    You are in turn forgetting that FTL drives are also time machines. They could come back and show it to us. Ooo looky, dark energy beams are collimated out here, well spank me with a kipper.


    Charles, I liked your article it was a good reminder of just how vast the scale of distance is between the stars not to mention inside our solar system. My opinion on interplanetary colonization is that it may be possible out to a few AU within my lifetime, but economic and political possibility are another matter entirely. Regarding interstellar colonization unless our understanding of the universe changes dramatically it doesn't look to likely to occur in my lifetime. That's not too say never though. It is possible someone will actually figure out how one of those hyper drives is supposed to work. Maybe they won't. Is the rest of the galaxy going to be happy with our view of manifest destiny? Who knows. That said I wouldn't mind seeing a unmanned interstellar probe to another star. They could turn a small moon into a mass driver similar to what took place in red mars trilogy. It doesn't even have to stop, it can just eject micro satellites with solar sails to slow down. We could use one of Mars moons they are close and its not ours :) Anyway thanks for the article.


    I say screw deceleration until we're dealing with the actual seed ship. Just make the robots and their cargo really durable and assume they'll stop when they smack into their destination. That also saves a lot of "slowing down at a reasonable rate" time that we'd otherwise be wasting.

    I know it's going to do a lot of damage to the planet that way but hell, that's what the robots are for, right?


    Interesting article. I completely agree with all of your points except for the propulsion bit (which I mostly agree with). The thing that you didn't take into account is the possibility of using what is essentially a big gun to give spacecraft a high initial velocity. Think about something along the lines of a particle accelerator but scaled to accelerate something large. By that I mean an electromagnetic gun that forms a ring.

    The craft may spend days, weeks, or months getting up to speed before it is let go and flies off tangentially.

    Another thing that I think could actually let people colonize space (even if it is only local space) is creating a ship similar to the one in Rendezvous with Rama, but built from wire produced from Iron-Nickel asteroids that is wrapped circumferentially (the end caps are built first). If one of the end caps can move outwards as more wire is wrapped on, then the ship could be grown as long as the supply of building material will allow.


    Funny article. I hope you get over your cold soon, so you can start thinking straight again. Funny comments too. Interesting how so many of them fall into the "who is to say what 10.000 years of scientific progress will bring" category :-)

    It seems somewhat arbitrary, using the term "magic wand" for anything not currently available at Walmart. How about technology that requires no real scientific breakthrough, only engineering progress? Such as nanotechnology.

    Ahh, nanotechnology. Taking out the cost of labor, and reducing the cost of engineering project to that of the initial design and of the materials and energy consumed. In space, where materials and energy are there for the taking, this reduces the cost of any project to the design cost. Regardless of scope.

    Imagine launching a small package to a tiny asteroid, landing machinery for gobbling it up and spitting out a small solar panel. That will be a huge design effort. Launching a similar package to a larger asteroid, gobbling it up and spitting out an array of solar panels with a combined surface area rivalling that of the earth, will be a slightly larger design effort - the material and energy costs will be the same. Uncanny resemblance to magic though.

    Or taking a number of asteroids apart, to build an array of electromagnetic rings, forming a solar-powered mass launcher that stretches across the solar system. Maybe 30AU. Maybe 100. The design effort involved in building one ring will certainly be immense. The effort involved in building an array of them, slightly larger. I can't be bothered to run the numbers, but one of those would be able to accelerate a decent sized payload to 90 or 99 or 99.9c, depending on how much energy you want to pump into it. A solar sail would then be used to brake a few years later, at the target star. Without invoking any new science even, just the the maturation of the engineering consequences of current science.

    Such a system would not have a magic 100% efficienty, although it could be damn close. But, as someone pointed out nearly 20 years ago, we can do better. We can send mass back and forth across interstellar distances, using next to no energy, and no magic. With a mass launcher at the destination, the same system can be used for braking the incoming mass, capturing back the energy pumped into it, minus slight losses, and used for the next outgoing acceleration. That is so close to magic, it might be called a free lunch. Or launch. Whatever :)


    Would we really send 200 living human beings which need many tons of stuff each?

    I think it's much more likely we'd send a bunch of DNA tubes, a cloning machine and a some robot "mothers".

    The reduces the weight/complexity of the ship by orders of magnitude - no life support, no food requirements, no medical/recreation facilities, etc., etc.

    DNA tubes also support big accelerations better and won't fight over the females or start rewiring the ship out of sheer boredom.


    220: i enjoyed reading your comment.

    @ charlie: Some of your thoughts are very profound. However, I think these thoughts are way too modern.

    Keep in mind the definition of modern refers to 'current' (not recent OR remote)


    The most amusng comments of the above are the ones lecturing Charlie fucking Stross on AI, nanotech and The Singularity. Seriously, even if Google and Wikipedia are too much effort, the very site you're reading this on has his bibliography for chrissake.


    Heres for all of you statistics peeps out there:

    Are you telling me that in your analysis about how big the universe is and how probable (or inprobable) intelligent life is, you couldnt consider the following:

    With the 5 billion people on this planet, and then figuring the billions that existed before us and the trillions that will exist after us that not one person is going to come up with an idea that we can follow to penetrate these problems of interstellar colonization?

    Sounds more like... maybe an 'earth' in a bunch of trillions of trillions of planets in the universe to me. (needle in a haystack, but oh wait the earth actually exists)


    "isn't so much a justification as an appeal to sentimentality, for in the hypothetical case of a planet-trashing catastrophe, we (who currently inhabit the surface of the Earth) are dead anyway. The future extinction of the human species cannot affect you if you are already dead: strictly speaking, it should be of no personal concern."

    -- ah... Charlie... a concern for one's descendants, and for the human race in general, is scarcely "sentimentality".

    I'm extremely concerned with the future of humanity, and even more concerned with smaller groups of increasing relationship to myself within that, and most concerned of all with the future of my nieces and nephews and grand-nieces and grand-nephews and their children.

    I'll gladly sacrifice a great deal of blood and treasure for them.

    Concern for 'generations yet to come' is one of the basic responsibilities of human life.


    Charlie: As for the $25,000 ticket, I could afford that tomorrow.

    "What will the neighbors be like"?

    Hell, my grandmother didn't have the slightest idea what the neighbors in Boston would be like; she'd never been more than 15 miles from the Wiltshire dairy-farming district where her family had lived for (literally) a thousand years. All she knew was that there were jobs available.

    And she didn't even get to Boston. Her ship hit an iceberg in the Gulf of St. Lawrence and she ended up in St. John's, Newfoundland, after the survivors were rescued. That's where she met my father's father.

    Virtually everyone who emigrated to early Virginia died. The average life expectancy in the first two generations was about 18 months. It took one hundred years before a self-sustaining population of English settlers was established there -- as late as 1707, well over half the adults were English-born.


    The conservatives only care/cared about space as a way to dominate the current world (space race to star wars e.g.)

    Not sure how the libertarians feel. Seems they would be fine with it so long as it's not the government paying for it? What am I missing here?

    Of course I agree 100% with your analysis, even though I've seen it presented many times before. The ultimate problem is the distance in reference to our lifespans and our inability to get along with one another over time. There's also a huge leap of faith being made in our ability to be confined to such a small space over what amounts to a lifetime. The physics limitations are no doubt the straw that breaks the camel's back, but the biological and mental challenges are extreme to the point of being ludicris.

    I still want to try to colonize Mars (that's as "doable" as it'll ever get). Right after we figure out how to pay for universal health care and then after we figure out how to create and spread enough wealth around that everybody is full, fat and happy. And when there's too much urban blight in Gobi City. Then we shoot for the stars.



    I talked myself out of this line of thought, but I should write it down.

    Living things do all kinds of stupid things all the time. From a future observer's perspective it doesn't really matter whether it is locally rational for a polity to blow 10% of GDP on some project. What matters is finding out that some god-forsaken island in the middle of the Pacific you can't really farm has a bunch of humans on it. So all we need is a future environment where energy is so cheap that a bunch of lunatics can afford to waste huge amounts of compactly-stored energy on an ideologically-driven irrational project as a side-show.

    Of course, at that point I realized those conditions also implied that the largest remaining city in the US was now Des Moines, and the Temple/Dome Of The Rock and the Kaaba had become research projects in nuclear salting.

    One half-singularity that might be worth thinking about is one where bugs derail IT, but access to dumb energy hits the sigmoid. Very Missile Gap; we don't need remotes much smarter than what we have to reduce the sun to near infrared. Perhaps another sysadmins-with-guns world.


    The idea that a human, because we will die, doesn't have a personal feeling for the survival of the human race is absurd. Not only did I have many wonderful philosophical discussions with my grandmother about the concept of extended family, mortality, and seeing history through relatives, I see in my sons' lives their future and I care about it EVEN THOUGH I WILL DIE. To think anything else would be to... discredit the will to create something of permanence, like great art, that will outlive the artist.


    "A large chunk of the problem I have with space colonization at current tech levels is that in terms of direct human experience there's no "there" there; just a succession of cramped metal rooms, some of which have windows with a view onto a place that will kill you stone dead in seconds if you ever break the glass."

    Why should they be small metal rooms? I'd think the way to build a space city is to start with a large, rocky asteroid and hollow it out--lots of solar energy to melt and bubble rock, or run rock crushers. If you can find a good source of the elements necessary to support life, the next thing I'd be doing is making dirt and planting fast-growing trees. (Shades of Heinlein.) Provided you had a reasonable connection with earth to stabilize the artificial ecosystem, I think you could probably get to a livable environment in about 10 years, and a comfortable one in about 100.


    Thank you for this excellent essay, which considers the problem in the correct way, in my opinion. Especially on this: "the conclusion I draw as a science fiction writer is that if interstellar colonization ever happens, it will not follow the pattern of historical colonization drives that are followed by mass emigration and trade between the colonies and the old home soil."

    The travel duration requires an enormous amount of energy if one wants to flirt with relativity to reduce the duration. In fact, with v=0.1c one still remains in “Newtonian��? orders of magnitude and the energy requirements remains very big. And if this shall be spent for a single astronaut, then indeed, there is nothing to obtain from such a project.

    On the other hand, we have a “human��? resource: time. Man must manufacture a vessel which cancels time :). I do not mean about a strange SF device but simply about a Nation. The nation is a place of life for which time does not count anymore. Men live within the Nation by working towards their own ends, of which a part contributes to the construction of the Nation itself. Centuries may pass, but the Nation continues its own way.

    Charlie, you evoke a generation ship of 200 people. You concluded from it that it is not easily bearable and that such project is doomed to failure. But what is impossible to 200 is possible to 10 000. One should not conclude only since it is difficult to 200, it is inevitably impossible by increasing manpower. For example, it is certainly more conceivable to 200 than to 1 alone, like is said at the beginning of the article. So let's continue on this way, and we will see.

    It is necessary to start from a small Nation and not from a tribe. A tribe is diluted in one century, and needs the contribution of neighbor tribes, that of which is obviously lacking in outer space. It is necessary to gain at least a factor 10 on travel timescale. It is number which stabilizes a society, its order, laws and institutions.

    At least starting from a "critical mass". One wants the smallest possible nation but which is a true nation. It is simply necessary to ask which is the smallest possible nation which is viable on a long historical term, of over one millenium, say. I think that the size of a antique cities gives us a reasonable order of magnitude : between 10 000 and 100 000. Let us negotiate it to 50 000 :) but it is the order of magnitude which counts (10^4 to 10^5). If one wants a better reasoned order of magnitude, one could start from Metcalfe's law which says that the usefulness of a network is proportional to the square of the number of users. A society is a kind of network, and its usefulness is the whole of the capacity of action and thinking which it offers to its members to satisfy their happiness.

    If the usefulness is not sufficient, the network must have another resource (women of another clan, for example…) if not, it ends. One can well conceive a threshold of individual happiness reached for a specific society size, at least for a certain duration. The "characteristic time" of a tribe of N=100 being 100 years, a state of manpower N=100 ² should bring us to 1000 years. It is what we need to reach a nearby system at the speed of ~0,01c.

    To shelter such a nation in total autonomy in respect to Earth requires certainly a vessel of dimension never considered before. But one should not get stop by that. At least, one can try to see what it would be possible to build while changing concept, because we can. Build a very large vessel requires energy and some mechanism able to build resistant structures starting from this energy. We have solar energy in abundance and a terrestrial biological inheritance able to build, thanks to this energy, strong structures like woody plants. If the action of the man simply consists in feeding a vegetable structure with molecules like H2O, CO2, NH3, P, S… resulting from the small bodies of the solar system, one has with photosynthesis an extraordinary lever to build a living organism in space, sufficiently solid and perennial to shelter a small humanity, without investing exaggeratedly in term of anthropic energy production. That would nevertheless constitute obviously a colossal project.

    In order of magnitude, it is necessary to imagine something like 10 km in diameter. It is an interesting order of magnitude because it meets two requirements. A cylinder of 10x10 km (diameter, length) has a surface of 314 km2, that is to say, for 50 000 inhabitants, a density of 160 inhab./km2, which is completely reasonable. Considered from the point of view of the numbers, one has the necessary place. Considered from the point of view of the individual, one is in a structure whose dimensions are of about size of the horizon available to the glance on the terrestrial sphere. In other words, the sight is similar to the one we have on Earth. Sure it is a closed environment. But at the scale of the individual, it is big enough.

    In a certain way, one can say that the minimal size of a Nation holds in what the glance may embrace, when calculating it well.

    From an architectural point of view, we could imagine double hollow vegetable fiber walls fed from the interior (in water, minerals, light) and forming a tight structure in rotation on itself to create gravity, an ocean of 25-30 m in depth floating on top of "continental plates" supported by ballast. The vessel mass would reach about 25 gigatons. To maintain such a structure, with enough luminous energy necessary to its maintenance (~1000 times larger than anthropic energy necessary to industry or the households) one needs to burn about 1 gram of deuterium a second (or of Helium3, but it is less available). Over one millenium, that represents about 30 000 tons. It is reasonable. It is not even too much.

    To move this structure towards a nearby system in a millenium requires a much larger energy. And there, I acknowledge that I am a little less optimistis. Some rather realistic innovations should nevertheless appear in the future. With chemical fuels, the impulse available is about 450s. With thermonuclear fusion we can reach 1 million seconds. It is reasonable to base the order of magnitude of our ambition on this value, at the same time for the propulsion, the fusible matter extraction and for the production of energy necessary to the ecosystem.

    But the essential is to conquer the "time factor": to build a nation which has "all its time", compared to the Earth. Without immediately speaking to move towards a stellar system, there is a first thing to consider to decide whether the project is perennial: if man manages to devote his efforts to transform 1 to 10 small bodies of the solar system (asteroids or comets) into a living structure, an Ark, then he has established definitively in space. He is already there for eternity, and that is not nothing, so long we ensure to obtain 30 tons per annum of fusible isotopes (or the equivalent in solar energy, as long as one did not leave the solar system). He then disposes of an arbitrarily long time to accumulate the fuel mass needed to join the first interesting stellar system, which does not need to include a viable planet "naked head": to colonize space, it is not inevitable to live on another planet. What is needed, is simply being able to live in space without time limits.

    Admittedly, to initiate such a project would represent a really colossal effort on the basis of our current socio-political situation. But I think that one can as of today considering and think about the "critical path" which would lead us to this goal.

    It would be a Nation which would undertake this goal for itself, and not a nation, or a coalition of nations which would undertake it for a tiny fraction of its members. It is very different. An organization like NASA financed by taxpayers can send a few tens of guys per annum in space. But here, the project constitutes the essential of a new Nation. Also, in addition to financing the NASA, the federal state or the states finance also infrastructures, school, justice, a lot of thing which constitute the life of the whole nation. There is a switch from 1 to 1000 at the level of resources. And not only the states are able to act: private individual can build houses, a society builds factories and all this contributes to the construction of the Nation. Within the framework of the Space Nation, it is not the legal status of the project which counts, but the fact that everything is devoted to the same structure, in the same structure. Therefore it can be only a nation.

    The critical path on the basis of the current state towards an autonomous Space Nation simply consists in letting a thousand people starting to work on such project, until they provide enough to their own needs to start building the Ark without claiming further resources from Earth.

    Gilgamesh "Interstellar Ark",


    Charlie, you are my personal hero and I will now buy all of your books in triplicate. :)

    Justin @237: nice summary.


    Before actually colonizing other planets, wouldn't it be just a grand idea to get our act together on this planet? Quite a number of challenges, right? No need to get into details, I hope...

    Space travel for the masses seems like a really stupid thing... An utter waste of precious resources!!! And, please, don't start yelling that not exploring space inhibits progress.

    However, apart from from my difficulty with how we take care of this planet, I love SF.


    The thesis of space colonisation being a non-starter is a reasonable one, for the short term, and given our current technology and societial norms. However I have no doubts that in the longer term (say 500 years) we will get there.

    Eventually greater longevity will alter our view on the feasibility of a 40-100 year trip. In a population of billions you will always be able to find volunteers, and in any thousand year period there will be people or groups affluent and crazy enough to fund it. Most probably for religion (ironically evolution seems to be currently selecting for religious fervour, the most fecund people in our hedonistic society are zealots)

    There is almost no chance that humans will be wiped out. Nuclear war won't do it, climate change won't have any noticeable effect on our population, disease will never kill off more than maybe a third to a half of our population even in a worst case scenario (deadly diseases make for poor propegators). We, or our children, meat or machine, are going to be here for the very very long term.

    Energy will not be a limiting factor even in the short term. A massive change is happening even now as we are almost without a doubt only maybe 20 years away from vast cheap utility scale solar (unless something even better comes along). Fission reactors are an easy and viable alternative with fuel available for millenia and we can already build fusion reactors should we need to. (the only problem is scale and cost, and that becomes easier in space with no gravity on the structure and no hugely loaded vacuum vessels to create). The levitated dipole reactor at MIT would be a doddle to adapt for space use, and would also make an excellent Bussard type brake at destination. Pulsed fusion/fission ala Orion (or Medusa for hydrogen bombs) concepts has fantastic performance for interstellar travel, with I believe Isp's approaching a million seconds possible. Fuel is so abundant it is ridiculous.

    If humans are going along for the ride then the ships will be enormous, this is also dictated by the physics and engineering of the propulsion systems we are currently capable of creating, and the need for biological shielding. This being the case we do not really even need planets habitable or otherwise at the destination star once we are happy living in interplanetary space. We can build what we want when we get there out of the scraps orbiting the star.

    There are also a lot of magic wands even now being hinted at: -Possible hints at gravity control (gravitomagnetic london moment measured in spinning superconducting disks in the last year). -Quantum nuclearites (weird epilineal earthquakes possibly produced by ultradense blobs of matter passing through the earth at 100's of km/s), what could we do with one of htose blobs if we caught it? -Robert Bussards/EMC2 possible breakthrough in creation of small clean fusion reactors, ideal for cheaper launch systems.

    I am less sanguine about antimatter. Far too difficult to store.

    By far the biggest factor that needs to be accounted for has got to be the coming of AI. Surely just a matter of time (20-100 years). It will alter our society so profoundly we can not even begin to imagine what we might be able to achieve as a result when a single person (in space) can potentially command or have at their disposal the economic equivalent output of a town or city or even country.

    I am not holding out any hope that intersteller colonisation will start in the next 300 years. But I would think it almost a certainty in the next 10000. Given enough people with the capability, and sufficient time it is bound to happen regardless of how uneconomic, stupid, boring or unappealing it might seem to us. Think monkeys and typewriters.

    Within 20-100 million years the galaxy will be fully populated by our progeny (whatever they may be).


    I agree completely that trade with colonies in other solar systems is unlikely to ever occur. But your comment essentially that "anything that happens after we die should be of no concern to us" is very much against what most people think. Most people try to leave an inheritance for their children, and educate them well, not for the immediate benefits, but for the thought that they are leaving something good behind. The purpose of galactic colonization is NOT trade, commerce. It is the dream that our children may remain once we die. Our sun will burn out, everyone believes this. If we want our descendants to survive, colonization is the only way.

    A slow generation ship could require a much more stable mini society and even perhaps a different human nature than is common today. Perhaps our only "children" will be robots. But, our culture is very different from the cavemen of the past. Someday, a culture that can send descendents to space may exist.


    Mankind has overcome many obstacles in the process of colonizing the earth. The biggest driving force to do that was either to conquer others, or to flee from the conquest. The problem with space colonization is there for also the existing problem of mankind - tribal diversity. Do you send a homogeneous group (same race, religion, language etc) to ensure harmony or do you send the best of the best of the best and risk exporting war and self destruction. Can you trust the colonists not to enslave some of their fellow travelers, or even to kill them to keep their tribe "pure"? Do you even try to preserve the cultures of earth? We may be able to overcome the science, but can we overcome the primal urge to kill what we do not understand or those who disagree with us, or even those we just do not like. Should space colonization be a human (worldwide) effort or do we leave it to individual nations? How will that change the composition of the space party? How long until space colonists declare independence from their home nations or declare war on the colonies of other nations. Do we first create a United Nation of the Universe and write a legal framework binding the colonist to earthbound rule? What will be the basis of law in space, and under whose jurisdiction will colonists fall? Will there be a separate Pope in each colony? How will you pray towards the Holy cities, or perform pilgrimage? Will the judgment day be universal?[ Flame bait: Any theologians out there?]
    I see a lot more questions that need looking at � questions that ignore reality and that are purely a manifestation of human evolution. But that is just another can of worms that needs to be addressed before we close the hatch and start the engines. Now shoot the messenger.


    I had a bit of trouble with the "you'll be dead so it shouldn't concern you" sentiment in the essay - our place and roll in the universe is bigger than our individual lives, and concern for posterity is one of the more redeeming features of human nature. On the other hand, until many other aspects of human nature are straightened out, it's probably just as well that there are barriers in place to prevent us being unleashed on Creation at large.


    I had a bit of trouble with the "you'll be dead so it shouldn't concern you" sentiment in the essay - our place and roll in the universe is bigger than our individual lives, and concern for posterity is one of the more redeeming features of human nature. On the other hand, until many other aspects of human nature are straightened out, it's probably just as well that there are barriers in place to prevent us being unleashed on Creation at large.


    First off, let me say: as an aspiring author myself, kudos to you for putting forth the effort, beating the incredibly bad odds, and not only getting published, but doing well enough to live off your craft. No matter what any critic ever says, that's an indisputable sign of great talent.

    Back on topic. :)

    One thing that you skimmed over here is how hard it is to actually colonize. You focus mainly on the transportation issues, yet "rebuilding society" on another planet is the hard part. Think of it this way: to survive on another planet, one is entirely dependent on modern technology. You don't have a working greenhouse, you die. You don't have oxygen production, you die. You don't have water extraction, you die. You can't expand your colony, you stagnate and eventually die. And so forth. So, we must be able to recreate modern industrial infrastructure.

    There's a problem, though. Modern infrastructure has a "long tail". You mine thousands of types of ores, make tens of thousands of chemicals in complex industrial processes, produce hundreds of thousands of types of parts with them, and millions of specific parts. Sure, if it came down to it, you can simplify to some degree. We could substitute polystyrene for polyethylene in some applications, for example. But substitution only goes so far. Try as you might, you'll never make polystyrene resist fluorine damage like teflon can, or act like rubber the way polybutadiene or neoprene can. No matter what we do, we're stuck with an incredibly massive industrial tail.

    Even if you potentially can make all of the products that you need, there's another issue: economics. While it's convenient to pretend that economics doesn't apply on other planets, the reality of the situation is that each colonist can only work so many hours of the day. If your colonists are out there chipping rock in space suits with pickaxes, there's no way they'll ever produce what they need in sufficient quantity to keep all of their systems running.

    On Earth, we were able to bootstrap to our modern industry. It took billions of people hundreds of years to do so, but we did it. Why were we able to? Because we didn't need our modern tech to survive. On another planet, we need modern tech just to survive. We can't bootstrap; the products of modern technology simply must be there.

    A while back, I started an analysis of the requirements for a true "colony" on Mars. I accidentally overwrote the document at one point, and consequently lost half of my work (which, in turn, was only a small fraction of what needed to be done). Currently, the document is mostly just some overviews of what is needed without going into specifics very much. Still, just from what is already accumulated, it gives a good idea of the scale of the challenge.

    Check it out if you feel like it:

    I may work on it some more later when I finish my current WIP. :) Not enough hours in the day for writing, coding FOSS, and in-depth research like the infrastructure paper right now.


    Who says we have to go in person. Perhaps we'll find a way convince something already out there to create some humans based on information we send them.


    Simply mind blowing.


    Hi All

    I always wondered why space travel never went anywhere in the 70,000 Centuries of Isaac Asimov's "End of Eternity" - they kept asking their computer-plexes what the easiest way to self-gratification was. Setting off for a new frontier implies a bucketload of dissatisfaction with the state of affairs at home. Comfortable societies and cultures of renunciation are the "Stay-at-Homes" who never change the world and worship the past.

    More seriously the real reason we're stuck here is that no one has yet managed to build a spaceship in their backyard. Once the Interplanetary Connestoga can emerge out of a nanotech vat in the backyard, space will be the domain of the uber-wealthy. Who are quite comfortable here on Earth.


    Adam @ 287:

    If I can build an interplanetary craft in my backyard, that means I can get and store a lot of energy very compactly. That kind of hobbyist capability implies that current dense coastal areas won't need quite so many postal codes.


    the current propulsion systems for space travel are primitive!

    look at rockets, ion engines etc, they work by the same principle as throwing a rock from a wagon, the reaction-counterreaction principle.

    Comparing this with current erath bound propulsion tech, we will surely see big improvements in propulsion systems for space travel.

    as hawkings said, it is also neesecery for our survival as a species to colonize the galaxy, since our solar system will go bye bye at some point and also other threats before that point.

    furthermore our insticts bid us to explore the universe, namely curiosity and our instict to keep ourselves from instiction. So of course we will see colonization in the future, nothing is impossible!


    For the unconvinced, check out what NASA has to say: space is indeed really, really big:

    Seriously, until we get to the magic wand breakthroughs, our "exploring" is no more than cave men splashing around in puddles.


    Check out the short story "Passages in the Void" which assumes there will never be any kind of magic wand technology and still finds a way for colonization:

    Introduction from the author: This story is what happened when I read a review of the provocative book Rare Earth which stated that, if the authors are correct, it means "the end of science fiction."

    This story combines every worst-case assumption from the Rare Earth theory with a nearly total absence of new high-tech modalities. Even if we are alone in the Universe, trapped by the speed of light, and beset by catastrophe, there will be stories to tell.


    Concerning space elevators. If future manufacturing technology brought the cost of making pure fullerine structures down to a mere billion dollars a mile (and considering a mile-high skyscraper would currently cost more), then a space elevator would cost something like 20 trillion dollars just for the actual structure. Therefore its unlikely to be cost effective for many centuries, especially when maintenance, protection from attacks and weather factors (wouldn't a 22000 mile long gold-coated carbon rod incite massive electrical activity in the upper atmosphere?) are taken into account.

    Oh well, here's hoping for anti-gravity...


    as far as the human immune system not being 'primed'... i dont think that will be a problem. the way our immune system works is by genetic recombination in order to protect us from the enormous number of hazardous molecules out there. We can make 10^9 different types of antibodies.. our bodies make them on the spot when we are infected. im a medical student and we learned this in immunology. also... the following is just a guess, we have no real way of knowing.. but extraterrestrial viruses wouldnt affect us at all because viruses depend on human cells to function and there would be no way for a virus to anticipate human cell machinery (virus coevolve with the host) same thing with bacteria, but to a lesser extent... most harmful bacteria have evolved to be harmful and evade our immune system... they secrete specific toxins and enzymes that are specifically targeted for certain molecules in our body. as far as parasites.. thats a possibility and same thing with fungus or some other life form that would "eat us from within"

    my take home message is that our immune system is never "primed" from the getgo... thats why kids always get chicken pox... if they were primed they would never get sick. we can make antibodies to accomodate 10^9 molecule conformations. thats pretty much everything you can think of in existence or not even possible. and also pathogens probably wouldnt even know how to hurt us.


    It's science fiction, wankers. And the point about science is that you can't fudge the science - it works, or it doesn't. All scientific achievements are based on this principle. Constraints are the precondition of creativity.


    Actually that's an argument on why the case for planetary colonization is weak - doesn't say much about SPACE colonization.

    Which is when you build your large enclosed spaceship, spin it for gravity, figure out all the stuff you have to know about physical and psychiological providing an environment that is stable for the very long term... and once you've got THAT set up quit worrying about a drive that'll take you light years away, and just park it somewhere useful in the habitable zone. When you run out of room build another one. People lose track of just how much ROOOOOOOM there is in the Solar System, even if you hang around the general area of Earth orbit. Even if you stay in the ecliptic (which you don't really have to do. Especially if you've got enough of a drive to change your orbit if need be to dodge Stuff in the way when you cross the ecliptic.) And at least you've still got the shelter of the heliosphere though we're still going to have to come up with some way of dealing with uncharged particles if we're going to live outside an atmosphere for any long time. Traditional approaches like keeping all your water in the outer shell may help.

    Why do this? Once you're out of the gravity well, you're halfway to the rest of the Solar System. Lotsa power available from that Big Fat Fusion Reactor in the middle of the system. Water - which also means oxygen, building materials and whatnot in small enough chunks you don't have to spend lots of energy hauuuling them laboriously into orbit. All the cubic you care to build. Stuff we haven't thought about yet. Maybe even stuff YOU haven't thought of yet. :)

    And I DO care what happens to the rest of the species even if human stupidity and/or a rock the size of Alaska renders Earth uninhabitable.


    James @247: I seem to remember a time when New Scientist was actually a fairly reputable publication, sort of a poor man's Nature. But that must have been 20 years ago at least ...


    Well gosh darn it its just too damn hard! Jeez, the maths is soooo good and the distances sooo vast and the logistical problems sooooo great that we really ought not to try at all. Whew! I feel better now!

    I think JFK said it best "We choose to go to the moon and do these other things NOT because they are EASY but because THEY ARE HARD!"

    Space colonization needs to happen, not because I am a hopeless optimist but because without it our chances of survival as a species is exactly 0%.

    Your current arguments simply highlight the fact that we cannot do it yet, not that it cannot be done.

    Get well soon and go back to the world of simply writing fiction instead of expounding crap.



    Isn't the real problem here that we can't write space opera using human characters, and that is incredibly frustrating for a writer?

    If/when the energy and other requirements are met for interstellar travel/colonization it won't be by the human race, but by its post-human descendants - a diverse set of peoples that will be beyond our comprehension in their capacities and motivations. (NB I don't buy the Singularity hypothesis per se, but won't get into that argument here - after all the problem is the same either way)

    The problem arises in any science fiction writing that goes beyond near-term thinking. For example presuming we ever do solve the problem of machine intelligence, and intelligence as such is scalable, how on earth does a writer write anything meaningful about AIs whose intelligence would quickly become supra-genius? You have to go with the Gibson approach of making them voodoo-like spirits or gods, which ultimately leads to deus ex machina plotlines in at least two senses.

    Dan Simmons's view of having a rump humanity busily massacring or being massacred by a variety of post-human species works for me, but the essential problem remains - whatever colonises the stars won't be us, and without a human connection it's damn difficult to write about.

    Summarising unpleasantly: aren't you just trolling because sci-fi is hard?

    Hope the hangover complements the cold nicely,



    S. M. Stirling @ 271:

    I think Charlie was writing in part to provoke a hypothetical audience of Libertarian Space Enthusiasts. Being libertarians, they would (ostensibly) believe that only the profit motive acting in individual human beings is responsible for progress. ("True development of space will only happen when we get the government bureaucracy of NASA out of the way and let entrepreneurs do it!") "Safeguarding the far-future human race" would not be a valid motive for these idealized libertarians.

    This provocation goes astray to the extent that: a) not all space-colonization enthusiasts are libertarians; b) not all libertarians match the idealization; c) people who don't fall into either category think that Chrlie is making a general statement about his own beliefs.


    146: "How much energy could we pick up en-route using slingshot type techniques?"

    (1) In our Solar System: not enough to make much difference.

    (2) If you start near a pair of supermassive black holes in mutual orbit, you can fling a payload the size of Earth -- in free fall! -- to a good percentage of the speed of light over a wide choice of directions. To brake, aim towards a second pair of black holes in mutual orbit, choose your terminal maneuvers carefully, and you can decelerate to a crawl with no more fuss.

    This was first described for mass audiences in my 2nd Omni cover article (the first, sold 1978 published 1979 having coined the term "Cybernetic War" now shortened to Cyberwar) (which 2nd article I vividly remember pitching to Ben Bova 28 years ago, after he'd rejected 5 more "sensisible" pitches and being surprised and delighted that he bought it):

    "Star Power for Supersocieties" [Omni, ed. Ben Bova and Robert Sheckley, Apr 1980] ISSN-0149-8711, $2.00

    This was the 1st popular article to predict a giant black hole in the center of Milky Way galaxy; and the 1st popular discussion of my invention "gravity wave telegraph" which may yet be our first successful SETI technology (you hear me, LIGO? LISA?)...

    My point, re: 146, the limits imposed by Physics (As We Know It) on human beings here and now have loopholes likely exploited by other entities very very far away, or our descendants (if you're optimistic) far in the future. Mr.Stroiss and I do not (to our knowledge) get paid for writing to an audience in some other galaxy, but very much hope (do correct me if I channel you inappropriately) that our remote descendents will read (upload/grok) our work with mixed amazement, pride, and pity.


    (I hereby pretend that "Mr.Stroiss" in #299 above was an intentional embedding of The Imaginary in the name of Mr.Stross, in deference to his prodigious imagination.)


    You still reading, Charlie? If so, (a) I'm impressed, and (b) note that Darien was not the exception: Plymouth was. Apart from a number of lucky breaks you can count on one hand (or two if you're being generous), hundreds of European expeditions to the New World were failures.

    Australia was known for a very long time before it was settled by Europeans. (Hint - who was Torres?) Why? Cos there was no there there.


    I am glad to see the delusion pointed out to an audience who has proven unable to arrive there on its own. Confusing space opera with futurology is an endemic problem and its not a recent one. I understood this when I was twelve. I had this argument with my Dad who was born in a poor working class suburb in 1942. I have reflected on this conversation over the years and realised that he saw me as some sort of pessimistic, defeatist, nihilist X-Generation figure. I was questioning a belief which for him was theistic: infinite growth, no boundaries, Moore's Law applied to all technology - forever...

    Just a really big bubble in the surrounding entropy I believe. Murphy's Laws of human nature will eventually prevail over Moore's Law applied to our technological development. And that's just the beginning. You think the rise and fall of empires is a product of ancient history or something Gibbon made up? Randolph in this comments thread included the quote: "We live in extremely interesting ancient times." And we can't even safely say there will be historians to write up the rise and fall of our little technological bubble.

    Why are the Baby Boomers so dependent on these beliefs? How about comment 18 saying that this essay represents some sort of failure of courage... It is more courageous to stare in the face of the finitude of our species and our global civilisation... than self delusion. But it isn't about courage - that's your red herring.

    I also note the similarity of space opera and the operatic visions of Wagnerian heroes which obsessed Adolf Hitler and many other Germans of his era. They also envisaged a beautiful semi-mythic pathway into the infinite for Germany. Vollmann's novel 'Europe Central' is a great source of info on this. I also note how great convincing these operatic themes are for writers of propaganda.

    The first commenter wrote:

    "Perhaps we'll have tech to digitize human minds, in that case we might have some actual people from earth to resurect into new bodies."

    I'm probably not in good company for saying such things but: - you've been reading far to much good sci fi and watching far too many bad science docos my friend. You don't have to be a theist to see how utterly misguided this idea is.


    1000 years ago trying to organize a manned flight to the moon would have been impossible. The very same unimaginable set of requirements would have been laid out as you have done so here. In 1000 years who knows.


    Reading on I see there are many who believe in mind uploading and Charlie you are either not feeling bold enough to slam this one or your mind also dabbles in this mystical and mysticism. Or perhaps this is your 'reel them in' strategy. My strategy would be cut the lines rather than reel them in but I get to comment so I can't complain...

    Where does mysticism get its lever? From the fact the basis of personhood is not understood. That lack of understanding is not just technical. It is ontological. Science cannot solve it until it re-merges with philosophy as in Aristotle's day. It was probably the divergence of science and philosophy which caused the 'mystical sciences', ala Thomas Acquinas and Descarte, to get so much power.

    Now none of you mind-uploading fans seem to have much in the way of philosophy. Or history. And it makes your futurology vapid. Which leads to the most boring space operas.

    A good sci-fi writer who knew all of this better than anyone ever is the recently deceased R.A.Lafferty.

    And is that you Dad on @62?


    Why would anyone want to live on the moon? Let's first build a giant "laser" on it! Or write "CHA" on it first!

    When will we read a nice terraforming article here?


    By far the biggest problem is not getting there, but enginnering an environment where humans wil willingly stay. Take Mars as an example: as an earthlike planet, it meets 90% of the requirements, size, distance from the sun, rotational rate etc are all reasonably within spec. What is needed is a few extra's, let's presume there is no usable quantity of water; why not steer a few large iceberg-comets into its path that will jack up the water supply and where there is plenty water, a good chance of some oxygen. Too cold? Send a few large rocky coments towards it, the collision could produce a reasonable amount of heat and get it's mass a bit higher and modify it's rotational rate to boot. After a few hundred years, you could have something reasonably inhabitable.

    Now think big, contruct your own small planet from space debris, while doing so, arrange the collisions so it gains speed, the required direction and the required balance of elements. Add a large nuclear/antimatter/whatever powersource and sent it on it's way to Proxima. Then pray a lot.


    How about a generation ship with only our genetic information, our seeds of our planet ?

    Terraform a remote world, then breed humans (let's do that at day 7)

    In the mean time we still can wonder if it would be wise again to devide us in male/female or that 7th day Adam first creation will be again a single bio-engineered self reproducing creature like he orignaly was. As it was written down in the first book of creation directions

    BTW how about a payment day for it all in the end, no dont argue it isnt a doomsday i't just return of genetic material acoording to our contract 1453978# / 23.1


    301: Yes. It's alarming the number of people here who seem to think they're going to space despite lacking reasonable reading comprehension and social skills.

    Seriously, there's no point thinking about things without setting limits. Otherwise it's just religion. Assume antimatter. Assume terraforming. Wank, wank, wank.


    The analysis is all very well for a spaceship that has to carry all its fuel and energy supplies with it. It fail however, if one can gather fuel on the way.

    If one uses a ram jet fueled by interstallar hydrogen, or some similar semi mystical power drive, then the game changes.

    If one can accelerate steadily at 1g, the after one year one is travelling as near as dammit at the speed of light. Lorentz contraction and time dilation are now serious. Do the arithmetic and you find that in 2-3 years proper(*) time a traveller can go as far as he likes, not just within the galaxy, but across the whole universe. Accelerate to the half way point (1 year and a little bit over), then decelerate to the destination (another year and a bit).

    Of course, for the people staying at home and waiting for the results of the probe it still takes a minimum of 200 years to get the results from a 100 light year trip. But for the traveller it is a long, but not impossible journey.

    (*) 'proper time' is time as measured by the traveller, not by the observer.


    If we keep thinking about settlement of other heavenly bodies in our own lifetime, it will never happen. What is needed, is for mankind to grow up. We will have to settle our differences, get planet Earth under control and achieve a sustainable future.

    Without that, we will not last long , even on Terra-firma, not even talking about seeding the Universe.

    The kind of resources required may very well require the collaboration of all nations on a thousand-year project.

    If that can be done, there may be some hope.


    gobi desert: rather than endlessly recycling tired and self-referential viking and samurai motifs, thousands of nerdy ST fans looking for "alien" inspiration could benefit from studying this region, populated by such interesting people as the mongols and kazakhs, the former of which were specifically mentioned by jon colicos as the main inspiration for his performance as the original klingon commander in the '60s and the latter famed for hunting with eagles as companions the way americans hunt with dogs


    [I'm back; funnily enough, I need to sleep at night ...]

    Thanks for your comments.

    I am forming another, still inchoate, hypothesis about why some people seem to respond to an enumeration of facts based on observation as if I'd told them Santa Claus was a lie, Bambi was dead, and the Baby Jesus wouldn't cry if they had a furtive hand-job.

    In a nutshell: this is fairly clearly a quasi-religious belief, and people tend to respond emotionally and angrily to having their religious beliefs mocked.

    More to the point, the libertarian/conservative nexus (that I didn't spend enough time taking the piss out of -- you can take my comments on the lack of cost-effectiveness of space colonization as being ironic sneering at the inconsistency of their world-view, if you like) is interesting. I note that there is no corresponding Christianist/space colonist nexus; however, fundamentalist protestantism and conservativism seem to go hand-in-glove in US politics this decade.

    Working hypothesis: take Americans raised in a conservative/religious tradition. Some of them start to question elements of their world view, notably the existence of the Invisible Sky Daddy; but they subconsciously feel the need for an ideological focus that provides a long-term teleological goal to replace joining their father in heaven. Space colonization pushes all the right emotional buttons -- it's a long term abstract goal, it's open ended, it's unfalsifiable, and there's scope for gaining personal kudos by advancing the crusade, and personal emotional fulfillment in daydreaming about it. So it coexists uneasily in the minds of conservatives and libertarians who've taken a first step towards distancing themselves from their formative environment, but who feel the chill empty wind of eternity blowing down their necks when they contemplate a purposeless universe.

    In other words, it's a nascent secular religion.

    (It also appeals to unsocialized ass-hats who attribute their personal problems to the existence of people who are Not Like Us, and who think that distance-enforced apartheid would be a good way to cope -- but that's another matter entirely, and rather sad.)


    Secondary thought:

    Before discussing the possibility of building space colonies (and yes, large rotating cylinders made out of materials mined from near-earth asteroids are a lot more plausible than terraforming Mars), it would be a good idea to examine just how difficult it is to manufacture a kilogram of fertile soil. This paper seems to contain some promising insights (if you ignore the knee-jerk ideological genuflection near the beginning).

    A mature understanding of ecosystems and environmental engineering is absolutely vital to any attempt at building an orbital colony (let alone terraforming). We aren't there, although -- unlike the picture in propulsion systems -- I see no obvious roadblocks if further research and development is pursued: but when you mention environmental engineering to most space settler cadets, they tend to dismiss it as a minor detail or an irrelevance.

    Indeed, there seems to be a large subset who believe that we need to colonize other worlds because it's a survival strategy for dealing with environmental degradation on this one. Which seems to beg the question of how we're going to create and maintain a habitable biosphere there if we can't even maintain a previously working one here!

    Anyone who's really serious about human space colonization is going to have to come to an accommodation with the Greens. And as the conservative/libertarian nexus I mentioned seems to view environmentalism as some kind of heretical rival, this could be a serious Problem.


    Almost 300 comments and so few mention the two most important points (IMHO, of course)

  • It can become possible in the future, but when you get 'there', you will be locked in a cell, with windows if you are very, very lucky. And you will stay in cells forever and ever, until you die.

  • Colonization has always been propelled by potential profit (of course, many schemes didn't succeed) and, as of now, we can't even think of anything profitable in space excepting sun power and we won't need to colonize anything to get it... mining asteroids?

  • Get real, we have barely started to scratch the surface of this planet!


    Charlie, I think you are overly pessimistic. Consider the Anthropic principle: we live on the perfect planet for us, in the perfect universe for us. I find it hard to comprehend that the universe we have been so blessed by, would confound us in the ways you seem to think it will.

    Your perspective is somewhat wrong in my view.

    Consider Evolution, and that humanity is biology's ultimate expression of manifestation: the self aware intelligent creature. Through Evolution, and specifically DNA, we now stand (almost) ready to leave biology behind and make new definitions of what it is to be human.

    I feel certain that biological humanity's lifespan from here forwards is fairly limited in geological time, but our human descendants who will not be biological, will be perfectly designed for the rigours of galactic civilisation (probably conquest, in fact). To them, time and distance will have little meaning, even if FTL is not forthcoming, and they will be capable of surviving in most of the galactic disc I imagine.

    They will think of themselves as human, and may toy with biology, but it is safe I think, to assume that the torch of Evolution will be passed from biological life to technology/hardware-based life in the near future; this is the singularity, or a reasonable facsimile of one.

    Once you accept that fragile air-breathing human bodies won't be the occupiers of the galaxy, it's easy to make the leap to believe our non-biological children will inherit what we now covet.


    There seem to be a lot of these asshats around. Or at least they are very noisy - I wonder what a Singularity of asshats is going to look like?


    stross's basic position here -- that shipping monkeys-in-tin-cans to nowhere-in-the-sky might be a silly use of resources, unjustified by real human motivations -- is in fact the majority position, both among educated people and the general population

    pick your audience carefully enough, you can get contemptuous abuse back for telling it the sky is blue and the sun will rise in the east tomorrow morning

    spend a year or two living on the street in minneapolis or even seattle, and the romance of proving your mettle against a hostile environment will wear off completely ... save yourself a trillion dollars on a space rocket, go to hawaii instead, squawk at a parrot and eat a banana


    Thank you for a very interesting article - while I enjoy the full-on "high fantasy" style of sci-fi (like the Ian M Banks stuff), I also really enjoy reading the work of an author who will try and get the hard stuff right and only wave the 'magic wand' when it's absolutely necessary for the plot. I've read 'Singularity Sky' and loved it, and I'm about halfway through 'Accelerando'.

    I've greatly enjoyed the comments on here, both from those who have put some thought into the comments and also from those who have seen their beloved "Buck Rogers" and "Star Trek" fantasies debunked. Nothing says 'well-considered response' more than the over use of exclamation marks. Many seem to equate the acceleration of technology with the redefinition of many physical laws. OK, so before Newton we didn't have much to say about gravitation, but the jump from Newton to Einstein wasn't really a rewrite but a refinement - so much of modern science has been experimentally reproduced over and over (and over) again. If we're going to have some new discovery that will open up the stars, I can't wait, but I'm not holding my breath.

    One of the most interesting aspects to me is the "group of people" generation ship type thing. One responder has already pointed out the possible advantages to sending a crew with autism - how about we send a crew of OCD sufferers? They'll keep the ship clean all the way there... And what sort of strange quasi-religious beliefs will they gave when they get there? And how galling would it be to spend 1,000 years as a group in a space-ship only to arrive and discover that someone had found FTL spaceflight shortly after you left and you've been beaten to your destination by a bunch of tourists? (I think 2000 AD has already done that story though)...

    Anyway, rambling over. Great article, love your work, get better soon and publish more!


    Dear Charlie @ 117 (re my 105),

    Hi, and thank you very much for your considered reply. Keeping up with 300 comments and another 600 from slashdot.. whew!

    But you got me mixed up with some other dude. I didn't use the phrase "the high frontier" repeatedly, that was your opening title. I used the word only once, in "Expanding our frontiers...".

    I agree with your assessment of practicality of colonisation in the near future based on current technology.I do not however believe we need holes in physics or to become robots to at least explore and build outposts within our own solar system. I don't know any of these colonisation enthusasts of whom you speak, perhaps they need better science teachers.

    Far be it from me to attempt to direct your work. I think I understand you slightly better now, and if I can trust you to always question assumptions, then that is enough. It just seemed to me and a bunch of other dogs on the net like something else was on your mind, you seemed so vehement and all. 900 posts now crying, "but you aren't counting on technology X and the Course of Time (tm)" must be quite frustrating as you try to tell it like it is.

    One /. quote was, "For a science fiction writer, he certainly seems to have limited his vision." I think that was my main point. I think I must have hit a real nerve with you though, your reaction is so strong. After all, a science fiction writer calling something like the Ringworld a "collectivist pie-in the-sky daydream". Well, sorry to have gotten under your skin..

    Personally, I certainly didn't intend to suggest you have any mystical responsibility to write fiction or believe in the potential of science, or anything like that. I don't think Heinlein indoctrinated me (though if he did I certainly enjoyed it, maybe that's why I've repurchased The Cat Who Walks Through Walls and Number of the Beast so many times over the years) and I do think your honesty in trying to poke holes in things is something people can respect after a while perhaps. Certainly you are distancing yourself from the handwaving that goes into much scifi, and I'm curious about what that will lead to.

    The way you went about it though felt a bit like a straw man superiority pose to me and a bunch of people, that's something you may want to watch out for in the future. That is, nobody is planning an interstellar voyage right now, anybody responsibly thinking about it is not criminally wasting significant resources doing so, and anyway it is ringingly clear that your assumptions will not in fact be the default used when people get around to it. That said, of course you are correct so long as the status quo is maintained.

    Anyway, I look forward to your future writing especially the hard science fiction. Personally I enjoy more constructive articles than this one, since I could not detect any purpose in the exercise beyond a disclaimer that your fiction writing is strictly for laughs, but I presume you felt a need to tear down the crumbly edifice before you pour your own foundations. I wish you well.

    Matt Rosin


    2. Colonization has always been propelled by potential profit (of course, many schemes didn't succeed) and, as of now, we can't even think of anything profitable in space excepting sun power and we won't need to colonize anything to get it... mining asteroids?

    European colonization in the last few hundred years has usually been driven by potential profit, yes. (The same would probably apply to most Arab colonies set up in East Africa, as well.) There have been other motives, however, as was the case for some of the Puritan settlements in New England, Quaker settlements in Pennsylvania, Anabaptist settlements, Zionism, etc.

    I would also suggest that "desire for your own land" or "desire to set up an independent settlement" isn't exactly the same as "desire for profit." It doesn't make much sense to describe Polynesian colonization efforts as "profit-driven," nor does that motive really apply to the Norse settlement of Iceland, and I doubt it applies to the settlement of Madagascar.


    315: Consider evolution, and the anthropic principle suddenly doesn't look terribly smart or interesting. They are pretty close to mutually exclusive.



    OCD sufferers? Actually, I wonder if astronauts, aircraft pilots, etc. with OCD can be properly considered 'sufferers'. Their behaviour can be considered not just sane, but the sanest given their dangerous work environment.


    Meanwhile, I've just read that SSI paper Charlie linked. Well, at least there'll be fish and chips!


    @322: Well, when I said sufferers maybe I should have said "people with" instead, although the few people I know with OCD seem to consider it a burden! But I completely get your point, and that's what I was (clumsily) alluding to - what behavioural/psychological traits that we consider abberrations in normal society would actually be a boon to a closed, small space-flight group? Aspergers, monomania, sociopathy - would they be deemed less 'abnormal' in this strange new world?


    Paraphrasing a number of comments: "You write science fiction and you write THIS? Aiiieeeee!"

    So? To write science fiction is not to believe in any particular mythos about the future - it's just a living.

    Still - any number of smart guys are writing about this blog entry and debunking the specifics. Not fanboys I might add but guys actually earning money doing this stuff for a living.


    Reading this again I see what jumped out at me the first time

    Space elevators, if we build them, will invalidate a lot of what I just said.

    Or to put it another way - "get to earth orbit and you're halfway to anywhere".


    The Journey is the Civilization.

    A journey to another star is easier if you transport the entire civilization on an enormous vessel which arrives generations later.

    As a SciFi writer, you should have mentioned Rama!



    324: Aspergers' perhaps, but would you honestly want to be in a spacecraft with a sociopath? What if the character traits that spaceflight favours were precisely the ones favoured by small, crowded environments on Earth: conformity, mediocrity, obedience to authority? It's a boring, boring, boring voyage to Alpha Centauri in that case..


    Dang! Does this mean that humans are gonna miss out on all that fun that all those UFO's are getting on Earth now? I was looking forward to cownapping some alien equilivent of cows on other planets and making those native aliens think we're kidnapping them for some anal probing or whatever the latest's traditional after all!

    Excellent essay! Cheers


    I found it funny that the arrogant dickhead quotient rocketed just after the slashdotting.

    Not surprising, just funny.


    Heh. That's more likely to stagnate Humanity.

    Anyway, I focus on the practical - orbital chemical and biological synthesis has a known and impressive payoff, when you use the mass figures for Humans from Bert Rutan, and realise you can loft big things into orbit with an unmanned rocket. (Then the humans go up and put it together)

    A NEO-asteroid capture mission is also possible with our current technology - even NASA is talking about visiting one within a decade...


    Well I don't have the authority to argue the technical points however...

    Firstly the movie Red Planet comes to mind. Why would we have to send 200 people for a generation ship? I mean sure that's how Kirk does it but seriously that's a huge number. Why not send a much smaller number, like a couple dozen? And as for the cruelty or ethic/moral issues of condemning these 20+ folks and all their progeny to a cosmic death under any number of catastrophic or horrendous unknown effects of life long space travel, what if the crew were only volunteers? And at that why not volunteers that come from a pool of the world's best minds (and genetics)?

    I mean revisiting the whole "master race" has its own ethical conundrums but the folks on this flight would need to be pretty sharp(whether its 20 or 200) and more importantly they would need to be able to handle the technology on board as well as develop and engineer new stuff. And hence the rules of normal human society would have to be thrown out the window for these folks. Obviously they would have to consent and there would have to be some seriously psychology-minded folks on board. Anthropologically I certain someone could figure out a system that would be relevant.

    And now for the magic wand...

    So historically scientists have repeatedly achieved science fiction, often within two or three generations time(sometimes less). In light of this I find it interesting to discuss science fiction as prophetic and ask which influences which more, sci-fi -> science or science -> sci-fi? Culturally it seems interesting to me that often the folks that inspire and/or develop cutting-edge technology seem to be fans of sci-fi as well(e.g. Arthur C. Clarke).

    Otherwise its a great exposition on the topic. Thanks.



    Brian @326: you might also note that I said "we will not get there with rocket ships". I don't think space elevators are a magic wand -- a space elevator on Earth is an enormous technical challenge and might eventually not prove feasible, but there's no reason not to use them for the Moon or Mars (the Lunar elevator proposals would run to L5, because there's no selenosynchronous orbit but the moon is tidally locked to the Earth, and we already have materials with an adequate tensile strength). And there isn't enough work currently focussing on the use of orbital tether systems in Earth orbit for grabbing sub-orbital payloads and giving them that last, energy-expensive nudge into LEO. If you couple that with David Brin's idea of electrodynamic propulsion using the Earth's geomagnetic field, then there may be a very cheap way of getting significant amounts of payload into LEO without needing either space elevators or rockets or magic wands.

    ... But it'll take a lot of R&D money to make it work, and we're already in danger of getting ourselves locked into existing paradigm development, as with nuclear reactor tech, where PWRs seem to have a commercial lock-in despite the manifest promises of modular pebble-bed designs.

    Matt @319: you can find a free creative commons-licensed downloadable version of my last-but-one SF novel here (didn't win a Hugo; did win a Locus award, picked up several other nominations). It might clue you in on where I'm really coming from, even though it makes liberal use of magic wands at various points.


    Charlie, thanks for a very refreshing reminder of the harshness of reality and how tiny, or minuscule, we really are. Your writing illuminates how special our Planet Earth-Ocean really is and how we need to care for it.

    The author Michael Crichton stated it clearly: “the greatest challenge facing mankind is the challenge of distinguishing reality from fantasy, truth from propaganda��?.

    I might add that it's important to distinguish "possible" or "magic wand" technologies from what can really be done.

    Just because something might be "possible" doesn't mean that it is real. Reality is a harsh mistress in all her glorious beauty after all. It takes a lot to move from the realm of possibility of a hypothesis to a theory that can be repeatedly demonstrated as having a high degree of correlation with reality.

    The magic wand of superluminar travel of Heim Theory - well really hypothesis since it's not yet been demonstrated to have any correlation with reality - is another example of how people seem to have a need to "believe" in magic. Whether the magic is a supernatural being or whether it's a means of travel to the stars that's beyond current physics and current engineering, it's the same, a belief bordering on the delusional if one thinks it's actually real before the evidence is in.

    Now I'm all for chasing possibilities such as new physics, but I'm also all for basing an understanding of the future of the human species - and the other species of Earth-Ocean - upon our demonstrated understanding of reality as it is now.

    I appreciate the hard edge to your writing and look forward to reading your novels incorporating hard science. Keep writing!

    All the best,



    If by "human" you mean purely biological systems with two arms, two legs, and a tendency to break if deprived of oxygen for more than a minute, then yes, humans will never colonize space. But if you mean something that reads and enjoys human literature, then I have to disagree. Posts 68, 84 and 117 touch on this, but I want to emphasis that no one should underestimate massive genetic engineering and/or cybernetics.

    Americans have various hesitancies, but the Soviets and the Chinese have already tried fiddling with the human seed stock; all you really need is a mindset that is ready to treat the intermediate stage humans as (literally) cattle. For starters, you'd want something the size of a jockey with the lungs of a Andian mountain dweller. Replace the legs with extra arms, and add chlorophyll to the blood and bat wings to take advantage of it. At a molecular level, you'd want to produce all 20 standard proteinogenic amino acids, not just 10, and possibly an ability to digest cellulose . Solve or sidestep calcium depletion, and you have someone who would feel very at home in space colony.

    And yet, these same hypothetical colonists would be born, suffer adolesence, marry, bear children, and die. They would presumaby understand and even enjoy the literature of Isaac Bashevis Singer (who, when asked why he wrote in Yiddish, replied that though it was poor in words for technology, it had all the words he needed for the subjects he wished to write about).

    I suspect that the same will be true of all of our descendants, whether they are wholly biological, as in my example, or if they are born with various cybernetic implants. Strong AI would be different: Once you have machines able to build a 20th Century Earth in a different solar system, you are left with the question of why they would want to. If the machines' "souls" are sufficiently "human", however, the question is irrelevant. I suspect that to be able to communicate with biological systems, strong AI will need its own Three Laws: All AIs must be born and have childhoods; all must be capable of love and compassion; and all must fear death. Given that, then I would be willing to say that "humans" will eventually colonize other star systems.


    I think all the points are moot unless we can get the travel time to be relatively short. The driving force for most things of this magnitude is cost-benefit. So, you send a factory in a can to some place that takes at least 2-5 years to even get to and then start building the factory to develop...say computers. By the time all of it is done, we produce a 20 year old technology based computer...which is worthless and basically makes the entire mission pointless to begin with. And even if a company/government is willing to do this anyways, the cost to send raw materials (assuming robots so no food and assuming the raw materials can't be found on the distant planet) would astronomical.

    So, all in all, there's no economical reason to colonize anywhere outside the planet until new travel technology is developed.


    If you're going to dissect all the shibboleths of Golden Age SF, don't give a free pass to "robots to raise the babies" as an element of the seedship concept. I see that as less likely than FTL. We've never tried interstellar travel; some magic wand might turn up. But we have millennia of data about turning human babies into functional adult humans. The process doesn't seem to be amenable to streamlining or automation. Anything short of human attention 24/7 (counting "on call for instant response" as attention) just doesn't work. In mass-production orphanages of the past death rates were over 90%, a lot of that from "failure to thrive" rather than specific ailments.

    To adapt your closing sentence: build a robotic system that can raise and socialize a litter of puppies, or one that can look after a human baby for 24 hours without human intervention -- then get back to me about seedships.

    Louann "insert standard Bujold plug here" Miller



    As mathematically convincing as your argument may be, I think you're failing to recognize a very essential piece of this puzzle: time. No one living today has the expertise or knowledge to predict what kinds of technologies our descendants will be capable of creating. Traveling to Gliese 581c seems impossible to us today, but that's because it is impossible for us today. Our current state of technological development is only the beginning. If our planet survives the next 50 years (which I admit is questionable), then we absolutely have the potential to discover some technology that we can't even conceive of right now that would allow us to travel at faster-than-light speeds, or instantaneously for that matter. If we doubt the scientific prowess of minds who have not been born yet, then it is less likely that we will give our children the tools they need to discover such technologies. We need to be hopeful that there are an infinite number of technologies, energy supplies, space vessels, or something else entirely that we simply don't have the ability to think of at our current stage of development. We are still evolving. I have no doubt that sometime in the future, humans will be able to come up with something that will allow us to colonize the galaxy. While I respect your knowledge and opinion Charlie, your ideas are centered around the paradigms of the 21st century. I agree that we do not have the ability to settle other planets in our lifetimes or our grandchildren's lifetimes, but no matter the genius of someone alive today, there will always be someone tomorrow who thinks of something they haven't.



    "...when you mention environmental engineering to most space settler cadets, they tend to dismiss it as a minor detail or an irrelevance."

    An insufficient number of space cadets are biologists or doctors as yet. This is a selection bias. When the results came in around 1960 that most worlds in the solar system were barren, biologists abandoned space as an interest. That has now reversed, but it means a whole generation of space enthusiasts were drawn overwhelmingly from the physical sciences. There aren't enough space docs or space biologists yet to make these points stick in their colleagues' heads. Believe me: I've tried.

    "Indeed, there seems to be a large subset who believe that we need to colonize other worlds because it's a survival strategy for dealing with environmental degradation on this one. Which seems to beg the question of how we're going to create and maintain a habitable biosphere there if we can't even maintain a previously working one here!"

    It gives you additional data points about how to manage ecosystems, data points the science desperately needs. The two can go hand in hand. Indeed it might be better to start with simple tasks; Earth is too big to analyze all at once. Even Biosphere 2 was a total disaster; we need something even simpler and more isolated... like a space station.

    The domination of space enthusiasm by the libertarian/conservative nexus is a passing thing. It is not going to last. It is, as you point out, a product of recent American history. Fifty years ago, the main ideologies pushing space were liberals and fascists. Thirty years ago, liberals and communists. Now it's conservatives and libertarians. Who knows what it will be later? The Chinese are making their push, and they're not starry eyed libertarians. What will they build? Profitable things, I assume...

    The further we get from the starting gate, the less ideologies will matter. The field will broaden as technology is developed and all sorts of memes will get attached. Just because the Christianists have not adopted space as a cause doesn't mean they won't -- see the (badly written) Zubrin tale "First Landing", where (spoiler warning!) a Martian colony abandoned by the government is supported by the Christianists instead. I'm not saying it's plausible at the moment; I'm saying it's not impossible.



    1: For a passive flyby, the limit to the boost you get is about twice the orbital velocity of the planet (I think. I always mess this one up). Note that by definition, you'll never actually get the full limit.

    For an Oberth (fall from infinity, do a burn at closest approach), it's the escape velocity at the point of burn. Again, it's a limit. If you dropped a rocket from the orbit of the Moon and did a 5 km/s burn at the Vescape = 10 km/s altitude around Earth, you'd get a delta vee of about 11 km/s, for a gain of 6 km/s over what your rocket by itself could do.

    This makes Venus (decent mass, high orbital velocity) and Jupiter (Huge mass, kind of a sucky orbital velocity) very interesting objects if you are trying to use low delta vee rockets to move stuff around the solar system.

    2: Insisting on a self-sufficient colony raises the technical bar so high, it guarentees the colony will never be built.


    I think you're right about rockets and their futility, etc.,etc. Just as covered wagons gave way to jets and (soon) spaceplanes, things unimaginable at the time of the covered wagon, so shall we see things unimaginable come to realization as we move into space. I personally think those things will travel in 5th (or higher) dimensional space (if you consider time as the 4th physical dimension). I can't explain it, but I can see it in my mind. String Theory and 11 Dimension Space (Brane Theory) hold the answers to how the human race will be able to colonize other star systems.


    337(hey, 1000 more comments and you're l337!): This is a function of the ugly whiff of male smartarsery drifting off the slashdot monkeys. Damn, we need more feminist SF.


    And I DO care what happens to the rest of the species even if human stupidity and/or a rock the size of Alaska renders Earth uninhabitable.

    I don't understand this argument. If you have the technology to build colonies in space or on the moon or mars, then surviving on earth following a nuclear holocaust or dinosaur killer asteroid should be easy. There are huge advantages to living on a planet with all its associated resources, even if the atmosphere is toxic and the biosphere exterminated. For anything short of a disaster that cracks the planet like an egg, Earth is clearly the safest place in the solar system.

    Short of planetary scale disaster (and probably even after that), earth is also the best place to live. There is more stuff that is interesting living under rocks in my backyard than there would be in the most elaborate of artificial habitats.


    2: Insisting on a self-sufficient colony raises the technical bar so high, it guarantees the colony will never be built.

    Among other things, it rules out much of the point of building one, because it obviates specialisation, comparative advantage, trade, and all that good stuff.


    "The future extinction of the human species cannot affect you if you are already dead: strictly speaking, it should be of no personal concern."

    Although the maths etc. below this comment seems fair enough (and I'm having some trouble believing that no-one's gone through the numbers before) I have to take issue with the throwaway nature of this comment. I nearly stopped reading because of it.

    It's fair to say that you won't deal with the ideology and stop there. You don't need to add something lightweight, throwaway and (ultimately) completely wrong like this and the rest of the paragraph it's in.

    There are plenty of practical reasons why we might want to consider relocating. I think suggesting (and then refuting) the idea that we would want to benefit economically is a straw man, as is suggesting that we might possibly have a personal stake in it given the timescales involved.

    To assert that we don't have a personal stake in the future of the species is like saying we don't have a personal stake in building schools. Why should I care how well-educated the next-but-one generation is? The level of their education is likely to be of no consequence to me personally. I don't understand why something should have to have an effect on me, personally, for it to be anything other than "quasi-religious" in motivation.

    Yes I can't see that far into the future. I cannot guarantee that I will have any descendents alive at that time. I can't guarantee that I'll like where the future human race that actually makes the step is going or why it's going there. I'm not 100% sure I like humanity now enough to conscience the idea of its infecting the rest of the galaxy, even very very slowly.

    But I'm human. I believe, with Donne, that, "I am involved in mankind". Not accepting a personal stake in the health (mental, physical or "spiritual") of humanity now and in the future for whatever reason (moral, philosophical or even religious) seems an absurdity. Otherwise why be a scientist or even an SF writer? Why do anything more long-term than finding food, shelter and a mate?


    Boy, talk about putting the 'dip' in 'dipshit'. You really have no faith in humanity, do you Chuckles?


    344: You'd think the general lack of self-sufficient communities on Earth and the standard of living in the ones that do exist would be a hint (Although I'll take an Old Order community over North Korea).


    Well, you did mention almost all possibilities, but forgot to mention a very important one. The whole arguement is based on the sole fact that mass needs energy (a lot) to speed up to 99.9% lightspeed. Einstein calculated that it's impossible to go the speed of light because mass would need an infinite source of energy to do so, there's the bottleneck.

    But, there is a theory that the effect of mass is produced by fast spinning/orbiting particles creating a so called gyroscopic effect. Find a way to slow down those particles and the effect is that the mass lessens, or better, lessens to practicly nothing. Then you won't need an infinite source of energy, a little bit of energy should be enough to propel the craft at insane speeds that could easily be faster than the speed of light.

    So the only problem is that mass needs energy, cancel the mass and there you have your craft capable of reaching Neptune in mere minutes...



    Hi Alexander (346),

    Having faith in humanity has nothing to do with the realities of space travel and colonization. Faith is a delusion that won't get you across the vast gap of space, or give you enough air to breath, or enough fuel to cross that vast gap, or solve the real problems of travel and colonization.

    "Belief" and "faith" are unscientific notions and while they may give you comfort they won't alter reality or what is possible to do in reality.

    I invite you to take the red pill and join reality were you will be welcomed.

    All the best,



    Sid @345, you might want to refer to my unpacking of that throw-away comment here.

    Jack @348: that falls into my category of "magic wands" (and you're about the tenth person to bring it up). Show me a repeatable experiment that does this, and sure, I'll light your cigar.


    'The future extinction of the human species cannot affect you if you are already dead: strictly speaking, it should be of no personal concern. '

    I'd just like to raise one thing about that point, namely that most people are quite concerned that their children and, by extension, their grandchildren, great-grandchildren, etc, will be better off than we are today. Thus it would seem to me that saving your descendents from extinction is of personal concern.


    JimNic @ 347, I wonder if there's a common mode of failure between the North American libertarian/gun nut "survivalist" thing and the space colony with no women/blacks/Jews/people who prefer a different flavour of Cheetos thing?

    One is basically "I'm going to build myself a bunker with 10 years' supply of biscuits and 100,000 rounds of ammunition, so there!", the other is "I'm going to build myself an entire self-sufficient spaceship, so there!"

    Self-sufficiency, as a rule, really sucks. Autonomy, well, that's rather different. But you'd think that people who exalt market economics would notice that, well, you need a market..


    348: Magic demassifying technology will not allow you to go faster than light. An easy way to think about this is to consider the fact that in every frame we can measure in, the speed of light in a vaccum is always the same (Experimental data supporting this goes back to frigging 1880s. Isn't 127 years long enough for it to percolate out into the public mind). That means that no matter what speed your measuring device is going, the speed of a photon relative to it will be the same.

    This is a measured fact and not open to debate.

    What this means is that if you hop in the DeMasserific 9000, accelerate at a million gees for a year and then fire a photon off in front of you, it will still be moving away from you at 300,000 km/s and therefore you cannot be going as fast as light, let alone faster.


    I can only compare backwards... If you had asked anyone about how easy it was to get to China, from northern europe, 300 or even 600 years ago. Most people would not have heard of China, and if they had, they would tell you that you would not likely come back alive.

    Today we achieve this by getting on an airplane, and waiting really long. more than 10 hours. If you for some reason didn't make it back alive, people would be amazed and enraged. (And China in a political snowstorm.)

    Who's to say... Give 300 more years, and I give you a bunch of magic wands.


    first of all, i have not read every comment but skimmed through most and maybe/probably it was already mentioned.

    Let's assume that FTL is not available.

    Is it not much more plausible to assume that our evolutionary and technologically development will led us to a state of humanity in which we will achieve some kind of posthuman state (immortality/stable society/world peace/no overpopulation/technology that stops planet killing events and so on) before we reach another star.

    Without FTL magic it is possible that such a society would colonize its home star but there would be now reason to leave it. You would lose all connections to you home star and what for? To see a planet that is different to your home, even if your tech can create anything your mind can think of on your home planet. You can observe the exoplanets that are in sight through gravitytelescopes and recreate them (virtually), bring them to you instead of going there.

    If you want specimens and probes then send AI drones.

    Once you reach the tech level to leave their are no reasons to leave anymore.


    The argument that space colonization won't happen due to the distances is not a good argument as it only pertains to our current technology.

    It would be like the Druids sailing to Brazil in a row boat (if they knew that Brazil existed). The technology at the time would have made the journey impossible. It was not until much later that technology would provide a means to get there. Even Columbia’s journey to the “new World��? was fraught with risk and naysayers.

    Never doubt how exponential technology is. The more we know, the more we know quicker. Just because something seems impossible now does not mean that it cannot be impossible tomorrow.

    I agree with your viewpoints when comparing to today’s technology. However, we are currently in a state of revolution in all areas of physics. I have read somewhere that if current research were to stop today, we would have 150 years of research to fully study everything we have learned within the last 10 years. I remember reading that in the late 90s so who knows what those estimated figures are actually like now.

    Colonizing Mars would not be profitable at this time. However, the knowledge acquired in how to sustain life on a distant outpost will be extremely valuable. Look how much was learned just from the Apollo missions. Were would out lives be without Velcro! �?�

    My main point is that we still need to try. Sure, we will fail most of the time, as in most things in life, but if we do not try and fail then we will never learn from our mistakes. That learning process will make future endeavors more stable.

    On the angle of money, economics are only important to consider when thinking of investors wanting to make a profit off of their investment. Just because something is a waste of money, it does not mean it should not be done. I have 2 children and make more money now than at any other point in my life. However, I am poorer than I have ever been in my whole life. Does that mean having children was a mistake? Absolutely not, it is the experience made it worth while.


    Thanks for an excellent essay. I've skimmed the comments above and I'm surprised at how idealistic some of the critics are. Science fiction writers aren't and shouldn't be blind visionaries with their head in the clouds. If you want that, read fantasy. Science Fiction writers should have a firm grounding, as you clearly do, of the issues. Then they can imagine what really must happen to overcome these obstacles.

    Probably the best thing I got from your essay was a much greater realization of the true distances we're talking about it. I think few people (including myself, until your essay) understand the magnitude of the distances involved.

    All that said, I do believe that space colonization will occur despite all the important hurdles you discuss. Why?

    You mentioned space elevators potentially changing the equation significantly. We are always only one scientific breakthrough away from changing the equation. That's what science fiction should do - imagine... what if there was this breakthrough or these breakthroughs - what kind of a society would that produce?

    As for your second argument about solar-system colonization (which would also apply even if there was a breakthrough in travel-speed), I'd say this: you recognize at the beginning of your essay this "quasi-religious" zeal for colonization, but I believe you dismiss that zeal too quickly. Colonization is never driven at its core for purely practical or economic reasons. The driving force is always that quasi-religious zeal that is built into humans at a very deep level. It's clear that space is the next step in that and despite the incredible obstacles, I think there's no doubt it must eventually happen.

    Thanks for helping clarify the issues and invoking so much emotion and thought (as evidenced by the number of posts!).


    Martin, that assumes that all my neighbours are happy with me. They won't be, Humans being Humans.


    @358: andrew maybe not with you but your posthuman descendants will live in peace and harmony (like hippies with linux-macs and without drugs, just kidding ;) )


    Nice little meme-brush fire we got here. Translating humans into digi-humans is the only way to go. Our fantasies of space travel can be supported far more easily in a VR environment, although I'm sure FTL and other transport systems will evolve out of the hyper-intellect of the Sigularity, or post-Singularity. If nothing else, our future selves will need to figure out long term survival stratagies, and being able to move away from trouble and to do so quickly will be a worthy goal. Besides, Herbert said this is a magical Universe and I think it may have been right. Who knows what could happen?




    Thanks for reading & replying! Didn't expect that. Must be a full-time job.

    I think maybe your context implies a lot of things which I'm unaware of. I'm sure what you're suggesting in the "unpacked" version is probably reasonable; I've no personal experience with which to debate the issue.

    Either way though I don't think it's necessarily the case that the motivation is quasi-religious. It's possible to be concerned for the future of mankind without any religious motives.

    Admittedly we are talking a long way into the future unless we invent that magic wand surprisingly soon. But even self-interest might play a part.

    Consider this: if I engage in a career as an artist/scientist/whatever with the aim of getting into the history books, even as the tiniest footnote, there has to be a humanity in order to have history books & hence remember me!

    Especially given that many talented people aren't recognised until some time after their death and many ideas don't come to fruition except under the correct circumstances it is intrinsic to my motivation that the species has a considerable future, preferably immortality on a species level.

    Naive, yes, but I don't think it's natural or even particularly easy (or wise) to have a limited view of how far into the future one cares about. Maybe in practice but not in principle.

    I suppose we could derive a functional form for how far into the future one should care (vaguely analogous to the "shadow of the future used to assess rationality in prisoners' dilemma type experiments etc. - possibly some work in evolution of animal behaviour is relevant also although I'm not aware of what's been done), based on the level of self interest etc. No doubt the asymptote is zero but how long is the tail?

    Of course without much to model this sort of thing on and limitations in how much the past might resemble the future I suppose it does become less-than-scientific in a way but at least it's not based on any worse assumptions than most science: we all have to assume that the future will resemble the past in some respects.


    To start off let me say that the article was quite interesting and thought provoking. The article really doesn't sway my optimism about space travel and colonization, but it definitely makes me think which is a good thing. I would also like to say that I haven't read all of the comments yet, though I'm trying to plow thru them in my spare time as some of these are equally enlightening.

    Now, for my purely non-professional (by non-professional I mean I am not a physicist, engineer, or philanthropist who has dealt with this in detail) rebuttal on the moon colony piece of your article. I agree with you that economics is the most powerful motivating factor for any large scale endeavor, and I feel a permanent moon base would absolutely qualify. From what I know of the moon, there is very little of value that we know of there. However, the moon makes a GREAT location for some reasons such as limited gravity to overcome for launching spacecraft, lack of an atmosphere to foul up with industrial byproducts unlike here on earth, and several other reasons. Additionally, the suspicion is that there is water to be found on the moon, crater ice I believe, that can minimize that particular issue.

    These items bring me to my real point. Asteroids. I read an article several years ago that stuck with me. One of the most enticing points of the article was the estimated worth of a large nickel/iron asteroid being somewhere in the neighborhood of $1 trillion US. This is a HUGE financial motivator. The moon base would make an ideal refining/processing facility for this. Imagine carving off chunks of this type of asteroid and simply slinging them at the moon. Collecting and then processing this material on the moon and then ferrying the refined materials back to Earth.

    I think this is a worthwhile financial endeavor. Obviously there are a lot of technological hurdles to overcome, but I honestly feel this could be an achievable goal within my lifetime. Furthermore, this could absolutely lead to the complete construction of larger spacecraft for exploration or colonization without having to again overcome Earth's gravity

    Just curious as to your thoughts on this. You've probably done more homework on this than I have.


    Having worked in the area of Tensor Analysis and relativity, I see no way possible to explore space without warping space or time. Right now it costs NASA about $1,000,000 a pound to launch something in orbit.

    Furthermore, the acceleration needed to reach .9 c, no human being could withstand. Any human that could survive a 4.5 light year trip to our nearest star - it would take them about 10 years for a round trip. However on earth about 28 years will have passed. Everyone on earh would be 18 yrs older than the astronaut. He would be completely out of sync and communication with the earth. He would be a 'lost' person.

    IMO science fiction is silly.


    The ObSF reference is Paul Theroux's O-Zone, which must surely have dominated Langford's 'As others see us' column for months when it came out. It's a classic future-set plot (actually more S+F than SF), which says that it's not your horrible smelly fannish sf by having a sub-plot of sf fans who have degenerated into being a strange cult, worshipping O'Neill. Or something. It was long ago.

    By the way, Charlie, if I was your agent, I'd get worried at phrases like "unsocialized ass-hats". More power to your keyboard because you're not letting that stop you.


    How odd, an attempt to impugn interstellar flight/colonization by using our current understanding of the universe along with present technology. You know, if you sail to far in one direction you will fall off the edge of the earth. Better take some strong magic along.


    Charlie @ 333: I don't think there is such a thing as a magic wand; there is only a series of incremental improvements. Life gets better by and by and no one notices.

    Check that - there are great leaps but they tend to be one-off deals not easily repeated. The Manhattan Project got us the Bomb, Apollo got us a handful of trips to the moon, but only because of specific circumstances of which everyone reading this is aware so it need not be dragged out for inspection.

    The immediate problem is to drop the cost of getting to orbit. I'll take space elevators, electrodynamic propulsion or magic swans pulling chariots of gold; I ain't proud.

    I work where I do (LiftPort) and advocate space elevators because I think it is likely they can be made to work with some care and effort. Also because this is something that I can to do make the world a better place.

    It beats sitting around and yawping about how screwed up everything is or how it should be done (hello Slashdot!).

    Having said that I'm well aware that terrestrial space elevators might never work. I'm not a fanatic just dedicated.


    Out of curiosity, what sort of energy outlay would it take to accomplish a reasonable Dyson Sphere? Would the Dyson Sphere make more sense as a means of bleeding off excess enthusiasm than, say, blasting colonists through limitless space to meet bug-eyed aliens? It would certainly take the eggs out of the one basket, effectively, given the stability of the Sphere itself.


    Much of your argument is based on economic reasons. Very little of our current world is doing things optimized for economics. As a matter of fact the amount of wasted resources is staggering. I find it hard to believe automobiles are the most efficient way of getting around for example. Or all of the money and energy wasted on failed startup companies. When you really look deep you realize there is a small group of individuals on this planet that have more money then god. I'm not talking Bill Gates, but people that make him look like a begger. IMF, Currency traders, Bankers, people behind the VC funds that have trillions, people who inherited the great fortunes of history that we never hear about. Just like with Columbus's discovery of America it took that level of person to decide to fund his expeditions. I suspect it will be this way with the other great journeys ahead for man kind.


    "Furthermore, the acceleration needed to reach .9 c, no human being could withstand. Any human that could survive a 4.5 light year trip to our nearest star - it would take them about 10 years for a round trip. However on earth about 28 years will have passed. Everyone on earh would be 18 yrs older than the astronaut. He would be completely out of sync and communication with the earth. He would be a 'lost' person."

    It's probably not a good idea to get your physics from Mary Doria Russell.

    First off, 0.9 C is a speed. It doesn't say anything about the acceleration used to reach it.

    Second, doesn't it bother you in the slighest that you have an 8.6 light year journey experiencing significant contraction at a speed that cannot be much more than 1/3rd of the speed of light on average, given that significant relativistic effects only show up when the relative velocity between the object being measured and the device measuring it are close to the speed of light?


    I'm not sure why FTL travel is necessary. A ship capable of housing a self-sustaining colony obviates the need for FTL travel, because they'll arrive eventually -- maybe several generations later, but eventually.

    The real challenge in that case is either finding a way to harvest dark energy, or having a colony that is so energy-efficient that it can sustain itself on the energy generated by the cosmic microwave background. As others have said, perhaps humans are not the organisms capable of doing this, because we are a quite inefficient form of life. But if we could create organisms (biological or mechanical or both) capable of doing this, we would succeed vicariously. Or we could somehow modify ourselves to become capable of doing so. Perhaps it would require cryogenics, because a carbon based life form that expends less energy at rest than the CMB provides is only fiction.


    I've read all of the comments and I'm impressed by the number of people who analogize our understanding of physical and technical possibilities today with those of hundreds or thousands of years ago. To those folks I have to say that you don't know enough about reality to express an opinion about the future. Our understanding may be incomplete but it is not equivalent to Zeus or Thor throws the lightning bolts we see in storms.


    Charlie @ 312: the libertarian/conservative nexus is interesting...

    In the US, Reagan-and-after ideology is a significant component of New Space/ People have been saying "we can do it cheaper than NASA" (and trying to raise money to prove it) since at least 1970. But the whole Space Frontier Foundation complex of "government is the problem, entrepreneurs are the solution, NASA is blocking our path to the stars" has taken hold only since the 1980s. I very much doubt that it would have acquired such scapegoating vigor absent the broader political context.

    (I say "scapegoating" not because I hold any strong brief for NASA, but because I think the ideology encourages an attitude of 'space isn't hard and expensive, we've just been going at it wrong.' That's great for rousing the believers and generating David vs. Goliath news coverage -- but a recipe for disillusionment when you finally admit that many of the reasons space is hard and expensive have little or nothing to do with the "public vs. private" schema.)


    Charlie, I'm truly impressed with your knowledge on this subject. My only comment is that even science fiction writers have failed to grasp with any accuracy an authentic glimpse of the future. I haven't read any of your works, so perhaps I'm mistaken, but my point is that we still don't understand the rules of our environment and we may make unprecedented leaps in technology in the future. Looking old SciFi movies from the 50-80's I don't think anyone forecasted the computer revolution with an sense of breadth.



    Please correct me if I'm wrong but your biggest problem with space travel is speed and cost?

    If the human race is 200,000 years old, and we've managed to move ourselves at up to 10,807 m/s in that time... Wouldn't it be safe to presume we'll find ways to go faster?

    If you look at our advances in recent years it's not exactly an idiotic belief that we'll continue to come up with new "magic wands" that previous generations didn't fathom were possible.


    Look at the technology curve for the last century or two man. Shorter spans for greater technological gain. Why does everyone assume the best way to seed galaxies is to send physical beings? Ray Kurzweil proposes that the next step is to do away with inefficient human bodies and AI the human experience. "Are robots going to take over the world? Yes, but they will be our children."
    I liked that at first but then I realized that an engineer needs a theorist. Kip Thorne needed Sagan to poke him in with "Given that you have an advanced civilization, really advanced, not held back by ineptitude, or politics, or anything other than the laws of physics, what might they be up to as a civilization? How would they travel?" Thus began the wormhole process etc. I submit that living as wet, inefficient humans is not the path to happiness. How much of your day do you spend doing things you hate (work, cleaning, etc) to enjoy the things that matter (family, your hobbies, learning, travel, wonder)? Digitize the human mind and augment it with all known knowledge. Then we can spend our time inventing music, and philosophy, science, love, happiness. Once digitized into an AI world (The Matrix * 10^10^10 complexity and realism) why does it matter how long things take? What does it matter if the AI is in a pod resting on the surface of Earth or in a giant ring siphoning magnetic field energy off of a blackhole on epochal time scales? E=MC2. Energy is mass. Mass is energy. If we harness pure energy we can create our own matter, and thus we only have to travel as far as the nearest huge energy source.


    Like I said on the blog, this thread nicely shows why American science fiction is dying off: the writers are realising space travel is hard and not much fun to write about while the readers just want their thumbsucking fantasies of how ftl travel being just around the corner and we will colonise the stars.


    Brian @366: space elevators are one of the key non-magic (but non-trivial) technologies that undermine the argument that space colonization isn't viable. (On the other hand, you'll note that at one point I summed up my position as "we aren't going there by rocket" :)

    I applaud your pragmatic attitude -- in contrast to the deluge of magical thinking and indignation that any questioning of sacred cows brings forth elsewhere in this discussion.


    Charlie, excellent article and comments. Here's a couple of thoughts I had.

    First, there have been many comments on spending the world military budget for space exploration. I submit, in all seriousness, that such a thing would be a sure sign of a post-human society. Not making fun of the idea, but it would seem from both archeology and recorded history that humans wouldn't do that.

    Second, your point on the environment of a space traveler is well taken. The best environment you could hope for would be like a nuclear submarine under the Arctic ice. For life.

    Getting people to sign on for that would be very difficult. Unless you did your recruiting someplace that has worse conditions. Hot bunking, two squares a day and a chance to see your children live in a tin can might look pretty good. Us Western people forget that life can be hard and ugly.

    Third, artificial intelligence. At the moment we are discovering just how hard a problem AI is. But let us not forget that the human brain is a physical structure that houses intelligence. Clearly there is a way to do it. You and I aren't going to live to see it, but given Moore's law and the amount of time and money being thrown at it, AI is possible.

    If you can grow a human brain in 9 months from two cells there's a way to do that with an AI too.

    That lets you load up a couple hundred pounds of goo into a dirty ice ball and fling it at Proxima Centauri where it will grow into something useful to send stuff back home in bulk. Given your math that could be done "fairly cheaply" if one used solar energy to run an autonomous launcher.

    As to why bother, I don't want to contemplate a society that -needs- physical resources from other star systems. That would mean you couldn't get iron or whatever unless it came from another star.

    Dyson sphere made out of carbon whisker running 10^80th post-humans in the Matrix needs some more RAM?


    Charlie -

    An excellent, thought-provoking essay.

    Colonization involves an immigrant population going into an area to exploit it in a manner or extent that it is not currently exploited. Your essay suggests that space colonization will not be colonization at all. We will have to have thoroughly exploited space by other means (robots and the like) prior to having the infrastructure necessary to build a human-livable environment. I would guess that this would take on the order of hundreds of years, not decades.

    In short - Europeans could colonize the Americas because there was a livable environment there first. We will have to build that environment before we can live in space.

    No space colonization soon - space exploitation instead?


    If we look at the problem from the point of view of today's physics I would have to agree with you. On the other hand, imagine a world that (if we don't destroy ourselves first) can use the power of biotechnology to cause things like space ships to build themselves with just a little help from DNA programmers and instead of launching our ships on the ends of huge fire crackers we use the repulsive power of electromagnetism pushing against this huge magnet we live on to lift the ship into space.

    In addition, there is no reason in this "age of spiritual machines" for a ship to be burdened with a crew when all you have to do is set up a system of storage for DNA that can be used to reconstruct human beings (and other beings) when the ship reaches a suitable destination, whether it takes 45 years or 105 years. A ship can be both a carrier and a being -- not needing a human to direct its functioning. At some point in the near future, machines will be made of DNA and can be both bigger and smarter than any human. If DNA can construct a human there is no reason why, in an age where DNA is programmable, we cannot induce it to shape itself into anything we want.

    Imagine, if you will, based on the technologies being developed in laboratories all over the world, a ship as large as a small town with a brain the size of a battle ship and no people inside to use up resources that will be needed on the ship's arrival at a preplanned destination.

    If we're too believe Ray Kurzweil, the technology to do all of these things will likely become available in this century. After all, it only took us ten years to figure out how to go from making flying kites that people could ride in to planting our footprints on the moon. Ray's calculations show us advancing a great deal faster and farther in this century than we did in the last.

    For these reasons and others, I see travel between the stars not as impossible but inevitable.

    Grant Callaghan


    "having a colony that is so energy-efficient that it can sustain itself on the energy generated by the cosmic microwave background."

    The laws of thermodynamics are weeping openly.

    If you're using the background temperature of the universe as your heat source, what are you using as a heat sink?


    The political element is an important one. Had Kennedy not been shot, and if the Apollo program had proceeded slightly more rapidly, it could still have been Kennedy, not Nixon, on the other end of the longest distance phone call. In other words, the political sponsors want some political capital from it. That Apollo was binned once public attention waned merely indicates that it served its political purpose around about the same time Armstrong took a second small step. The same syndrome manifests in the near cancellation of the Voyager Interstellar Mission, a program that costs about $4.2mn per year out of NASA's $16bn budget - or 0.025%, or 1.4 cents per man, woman and child in the US - per year! Hubble gets away with it because of those stunning crowd-pleasing (hence space-politically relevant) photos, serendipitously produced at the same time as relevant science is done. Once political capital has been spent, science has a hard job bootstrapping itself as justification for the continuation of a space program. Leaving aside your technical issues, Charlie, I would say that even if they were addressed, as you assume, the lack of political payback for a colonisation mission which would simply trundle/race off into the void, reporting back every few months with "Wow! Space is really empty!" or "Look! Jupiter/Saturn/Neptune/Uranus/Pluto/a comet!" or "Mom! Dad! I still miss you!", ultimately never to be heard from again (thank God after months or years of that drivel, eh?), would surely doom such a project from the get-go, assuming there's anything like the current political and economic setup around at the time it gets laid on the table as a serious plan.


    Searching the through the comments I found no impulse by the presenter to argue against the eventual possibility of human society reaching a technological singularity. It is stated somewhat obliquely that such an outcome is not certain, due to potential for catastrophe, though no real prognostications as to the outcome (or percentage chances) is given.

    Given that, could this article be fairly summarized as, "Radical transhumanism must be achieved and adopted before direct manipulation of beyond-Earth resources can be initiated in a feasible and sustainable manner"?

    That is not nearly so provocative (in the argumentative sense) as the author clearly intended his actual comments to be, yet seems about equivalent; I, and probably many others, would jump at the chance to be a sentient starship as quickly as we would decline the chance to be accelerated through space in a capsule (from article) while retaining our current human biology.

    As context to this question, I have read and thoroughly enjoyed both Singularity Sky and Accelerando.

    384: Boy, talk about putting the 'dip' in 'dipshit'. You really have no faith in humanity, do you Chuckles?

    I think he has more 'faith' in the the fundamental science that precludes such activity.

    Arthur Clarke said that any sufficiently advanced technology is indistinguishable from magic. While I remember that quote, I do not remember where Clarke stood in relation to the discussion at hand. One thing I think needs to be pointed out here (and I've read most of these comments and haven't noticed it yet): If we assume that we'll ever get smart enough to solve the FTL problem (the biggest one IMHO), then we're likely going to be smart enough to create any substance we need or are short of right here on Earth out of nothing more than what they're created of now (protons, neutrons, etc). The idea that we'd go half way across the galaxy in search of some 'scarce' material is ridiculous from this angle. The same limitless free energy necessary for such a long flight could be put to a more immediate and practical use right here.

    Reshuffling our biology into silicon is intriguing and may eventually come to pass, but the only reason in the long run that we'd ever NEED to leave Earth is if the Sun failed. Some have pointed out how much easier it would be to alleviate an asteroid collision with Earth relative to leaving the solar system (or relocating to Mars). I wonder what would happen if an asteroid collision of significantly destructive punch took out Saturn, Mars or Jupiter: Wouldn't Earth's orbit be changed enough to cause calamity by the resultant change in relative gravity and the shift in orbital position around the Sun? Not sure on that one, but might it be necessary to build defenses against loss of those other planets as well?

    Best thread of the month that I've seen so far BTW.


    385: From Comment 383 which was probably being composed while I was working on 384!) before direct manipulation of beyond-Earth resources

    There we go with the 'beyond Earth resources' meme again!! Exactly which particles are we short of here on Earth!!! This IS NOT A PROBLEM of resource scarcity on Earth whatever other arguments are going to be made.



    (364) By the way, Charlie, if I was your agent, I'd get worried at phrases like "unsocialized ass-hats".

    I imagine that Charlie's agent has better things to do than worry about sundry offended numpties telling all/both their friends not to buy any of Charlie's books.


    Imagine a computation that would take 100 years to complete, on a cluster of 100,000 high-end mainframes. No matter how valuable the result might be, no one in their right mind would attempt to start the calculation now - because the computers available in 10 years' time will be about 10 times faster than the ones we have now.

    Sending a starship - whether carrying a robotic payload or a small village - on a journey of 400 years is a bad idea right now, for the same reasons. It would be overtaken by the starship that we send 100 years later.

    It is entirely plausible that within 1,000 years, if we last that long, we will indeed have outrageous amounts of cheap energy (between Kardeshev Types I and II), and the ability to convert it to antimatter in sufficient quantities to fuel starships.

    But of course the Singularity will have happened by then, as Charles well knows. @136 hints that one of the themes in Accelerando is that refugees will leave Earth to escape from the Singularity. Everything depends on how far space technology will have progressed by the time of the big S.


    Hehe, I bet in 1930 some crazy guy said "wouldn't it be great if we could transport a movie reel or a million pages of writing across the face of the earth in mere seconds. Some scientist would have said "that's cray, do you have any idea the knid of forces required to propell a movie reel that far so quickly? It's impossible I tell you!"

    Little did he know, just around the corner was the internet. I'm not saying you're wrong of course, but I'm optimistic for what man can achieve in the next hundred years.


    Accelerating returns, paradigm shifts, and the singularity, perhaps?

    Vitrification seems like a good (and relatively proven) option for interstellar travel; although, life extension research might catch up to that soon enough (hurry up Aubrey).

    Speed and other physics-bending technologies may not be such a deciding factor. AI/robotics is definitely not the way to go - totally no fun for us thrill-seeking bags of mostly water!


    I stopped taking you seriously when you said that space tourism to the moon would cost $1 million and therefore was not going to happen, when people have already spent $10-12 million to visit the space station as tourists. You also avoided many promising technologies and longer term goals in a bit of nihilistic narcissism (If you won't live long enough to see it, it might as well not exist... Hmmm... Childless much?) to the point where, much as with most arguments with such post-modern thinkers, one is forced to ask, "Are you deliberately cherrypicking your data or are you just ignorant of the data set at hand?"


    I'm surprised this hasn't reached the notorious Fandom Wank yet.

    Using past performance to predict that our technology will find a way to make interstellar travel et al strikes me as a flawed assumption. We don't have the data to support it. We may very well see all sorts of great scientific discoveries that allow such things, but its also possible that what is technologically do-able with the resources we have on this planet is about to reach its limit. We won't know until either the next huge breakthrough occurs or we hit the wall and things grind to a halt.


    (384)I wonder what would happen if an asteroid collision of significantly destructive punch took out Saturn, Mars or Jupiter: Wouldn't Earth's orbit be changed enough to cause calamity by the resultant change in relative gravity and the shift in orbital position around the Sun?

    Calling something big enough to "take out" (?) Mars (let alone Saturn or Jupiter) an asteroid is a little nonstandard IMO.


    Tim Fuller:

    Perhaps I made a less than optimal wording choice there, given the context of the discussion. I am not referring to resource use in the colonial sense, the "funnel resources back along the exploration chain to Earth" direction. I agree with your premise that any augmented intelligence capable of solving sustainable space habitation would not require farming other places for "fuel" or using the uninhabited regions to keep social and economic pressures from disastrous consequences - better solutions will almost certainly be obvious.

    Not knowing myself what such an augmented consciousness is like, I can only offer possibilities that might lead to, as an example, rendering a wandering asteroid into a unique machine intelligence via direct contact.

    What I am presupposing is that a mind significantly improved from my own will not only contain aesthetic interests but that those interests will be applied on a grander scale than my own, given the level of its abilities. Some authors (including Stross) have presented a grand vision of transmuting all the matter in space into "smart matter," though one need not embrace that vision to accept that smaller acts may be engaged in a similar way. Perhaps a future intelligence simply wants to do astronomy from the Oort Cloud for a century or two; maybe a long journey to another solar system is simply the multitasking backdrop to long-term examinations of mathematical or philosophic questions in a relatively quiet and undisturbed environment.

    In brief, perhaps art, rather than acquisition, has a place in discussing future transhumanist travel outside the local Earth region.


    I forgot to mention SETI as a low-funding requirement space program with zero political elbows. Sagan's "Contact" is an example of the space-political process gone wrong. Ellie's experiences in the transport system are subjective and undocumented, and from outside the module can only have lasted as long as it took to drop straight to the water. I think Sagan hits the nail straight on the head when he paints her political masters as being transfixed by this. "We spent $500bn on a funfair ride, which didn't work properly, for a single passenger, but expect us to believe some nonsense about wormholes on your say-so?". Sagan's hopeful coda is, of course, the 18 hours of static on the tape which adds a certain credibility to her claims and ensures continued funding for her SETI project ... yeah, right.


    I have a question for all you folks talking about terraforming Mars:

    How do you plan on keeping the atmosphere from boiling off the planet?

    Someone may have already addressed this, but after a cursory sifting through almost 400 comments, I haven't seen it.


    No space colonization (exoplanets) at all with our current technology and the technology you can extrapolate from it.

    Under the above premise current time humans will never be able to build some kind of FTL without a 'magic wand' technology.

    Maybe a generation ship could be possible with the extrapolated tech but the next problem would be a stable society of 200 or more people that would have to breed on journey that will take maybe 200 to 400 years.

    Only a stable, united world society would be able to build such a ship, but

    Who would want to leave if you and your children and your grandchildren will never see the destination? You would doom your children to live in a artificial environment for their entire life. Even if i were immortal or could live 1000 years i would not want to spend my life on this ship with only 200 to 500 people.

    Who would want to leave if it is not guaranteed that the destination is not hostile/poisonous (think of microorganisms/alien intelligence)?

    What happens if the second or third generation does not want to go to the destination anymore but back to the stable world society back on earth? You could only prevent this by hidding the existence of a nearby habitable planet (earth) or pretending that earth is destroyed/uninhabitable.

    I could not go on such a ship and doom my children to die there, the only reason would be if earth would be going to be destroyed. But if such a planet killing event would occur i think it would be already to late to build a generation ship, something that in itself would take generations.

    But if some kind of singularity occurs and a magic wand is found than i think we can not even imagine what the future does hold for humanity.


    387: "It is entirely plausible that within 1,000 years, if we last that long, we will indeed have outrageous amounts of cheap energy (between Kardeshev Types I and II"

    An interesting thing about dyson swarms is that potentially, they offer a way to power spacecraft remotely. The trick is to set up a phased array of emitters across the face of the swarm so that the effective diameter of the radiator is 2 AU. This would let you target rather small rectennas and power spacecraft without having to have a powerplant with you.

    The other interesting thing about dyson swarm/emitter combinations is if you use all of the sun's output in the beam and if the frequency you choose is in 400 nanometers, the beam can evaporate an Earthlike planet in about a week and it can do this at ranges of up to a million light-years.

    It can target Jupiter at ranges of up to 11 million light years (Although it will take six years at the least to dismantle the planet) and a star like the Sun at up to 110 million light years (Although obviously that cannot disrupt the star).


    @ 384: I wonder what would happen if an asteroid collision of significantly destructive punch took out Saturn, Mars or Jupiter: Wouldn't Earth's orbit be changed enough to cause calamity by the resultant change in relative gravity and the shift in orbital position around the Sun?

    To first order, no. If you magically removed Jupiter, you would probably get some small, long-term changes in the Earth's orbital elements which could conceivably alter things like the ice-age timings, but it would take thousands of years to begin to notice any changes. The Earth's orbit is overwhelmingly determined by the Sun's gravity, and secondarily by the Moon's.

    Leaving aside the fact that there's nothing in the Solar System big enough to "take out" Mars except another one of the planets (which aren't going to be wandering out of their orbits anytime soon), and nothing that could bother Saturn or Jupiter.


    The recent discovery of living organisms capable of growing on ionizing radiation may be very useful for any space based travel.

    Also, in the spirit of game theory, I believe one should not discount the importance of military considerations. Plausibly if having ready access to space gives one nation/military an unassailable advantage then an space-based arms race may follow. Though economically irresponsible it provides a convincingly good short term practical/political/social motivator. This may be sufficient to expand human "control" over the solar system. Whether this coincides with human expansion/colonization is debatable and may hinge of the cost effectiveness of short term advances in tech.

    If military motivations are reasonable, it does raise an interesting question. What would mankind do if SETI found something? Would that motivate us? Maybe it depends on the message and how far away it came from.


    398: "Leaving aside the fact that there's nothing in the Solar System big enough to "take out" Mars except another one of the planets (which aren't going to be wandering out of their orbits anytime soon), and nothing that could bother Saturn or Jupiter."

    Another way to look at it is that since the energy involved in disrupting Jupiter is equal to years of output, the effects of that portion of the impact energy that is expressed as heat and light might well prove problematic at 5 AU distance.

    Say the total impact energy involved is 10^35 Joules and 1% of that is expressed as light or heat. At 5 AU, each square meter would be receiving 10^8 Joules or about equal to the amount of light we get from the sun over the course of three months. If the sun is not directly between us and Jupiter, long term orbital consequences of its disruption will not be the first problem that we will have to confront.

    If we are on the other side, then we need to worry about what 300 Earth-masses of debris are doing.


    Catfish, #339. "An insufficient number of space cadets are biologists or doctors as yet. This is a selection bias."

    There also are scarcely any women. That alone ought to tell us that this ideology has problems. In fact, one of the biggest artistic problems that Heinlein avoided by distorting the characters of his women was that most women don't buy in.


    I doubt you'll get this far in the comments, #370 ye gods, but if you do here's your reward: a really good story idea!

    You mentioned "a camping kit that encapsulates all the necessary technologies and information to rebuild a human civilization ... self-replicating, self-repairing robotic hardware..." and several other people have talked about sending out such robotic colonizers. It doesn't seem to occur to anyone that, to any inhabitants of the target system, such a colonizer amounts to nothing but a very nasty plague!

    Here's the story idea: somebody else has been sending out robotic colonizers and one of them has arrived here. First thing we notice is, Ceres seems to have changed its albedo... something odd is happening to Deimos... what in the world is happening to Saturn's rings...

    Such a colonizer should have only minimal defensive abilities and in fact, be pretty stupid -- but it represents a technology several generations beyond our own. Given current technology, how would we respond?


    Doug R @399: if SETI finds something verifiable, then All Bets Are Off. On the other hand, I'm not sanguine about the probability. Leaving aside Nick Bostrom's simulation argument, it appears that we are living in the early years of this universe -- it's only 14.5 gigayears old, but, barring a Quintessence-driven "big rip', it's good for at least 100Gy, and possibly several orders of magnitude longer than that. In this context, the silent skies and the Fermi paradox have a simple answer: we may not be the first intelligent civilization to show up, but none of the others have succeeded in not only getting out of their own solar systems but doing so and prospering on a cosmological scale.

    (Or I could be full of shit, and Robert Bradbury is right: the ETs are out there, and they're so out there that we've noticed them already and mistaken them for gross astronomical phenomena. I'm not sure which would be worse: we're the first and only, or we're cockroaches living under a kitchen sink and we don't even realize there's a city around us.)


    The only thing which would make people seriously consider sending anything out into interstellar space would be the confirmed discovery of an Earth-like planet (if Astronomy became refined enough). If it became as "simple" enough as an engineering problem (like space elevators, for example) to get there, a way might be found over decades or centuries. But the ethical problem of superimposing Earth life over another planet's life would arise, as an intelligent species might arise if the planet was left alone (eg. some alien species could have decided to colonise Earth a billion years ago).

    In all this well-written article may highlight why it doesn't appear to be Star Trek out there and why we've been undisturbed for 4.6 billions years and probably 4.6 billion more had intelligent life not evolved on Earth at this point.

    What if the nearest intelligent species is 1500 light years away?


    I'm sorry but your argument is like saying what we can't do now, we never can do. So many have come before and made such similar arguments. There are just too many unknowns for a reliable prediction of what we cannot do in 100 years. While I do not believe we will effectively break the speed of light and I am not a proponent of "magic wands" A Bussard ramjet in theory could achieve a significant portion of the speed of light, and while there are many technologies to master before something like that becomes practical it is hardly in the "impossible category". Your credulity reminds me of Robert Lusser who declared based on his calculations, "Man can never go to the moon, let alone Mars." Yet mankind did that, and they did it in 1969, the year he died.

    There is a veiled assumption in your argument that everyone who disagrees with you must be delusion fantasist or unable to grasp the concept of the distances involved. Yet there are many scientists who very well understand the distances involved and put forward the argument that not only will we be able to move mankind outside of this egg-basket but we should. Your pessimism is noted. I'll continue to be open-minded and interested in what we can do that people thought we'd never do.


    dcortesi, well, if you assume that it's fairly hostile, it's already been written. Quite recently, actually - Von Neumann's War, Ringo and Taylor.

    martin, hibernation technology is perfectly plausible in the near future. Look at the recent case of a (japanese?) businessman who survived in a very cold situation by what would appear to be a hibernation mechanism...

    So you can sleep the journey away.


    397: Good lord. A death star indeed.

    Now I really want to see a cheap-energy failed-Singularity story.


    The basic premise of the article is correct, albeit inflammatory (I suppose that was part of the point). It's easy to forget that "research" and "development" are very different things. To be fair, the fact that we scientist types lump them together ("R&D") doesn't help. "Development" is when you know enough to put a concrete, viable plan in place to achieve a goal. "Research" is when you need new fundamental discoveries ("magic") to make the goal viable. Really the test is whether a reasonable person accepts a given plan and timetable as credible or not.

    Apollo in 1962 was a development project. Yes there were an enormous number of engineering details to get right and systems to scale up, but the underlying technologies were proven. There were no matters of principle at play (except perhaps the worry that the lunar lander might sink down into a thick layer of moon dust and never be seen again). By contrast, room-temperature superconductivity and space elevators are currently research. Nobody knows when or if these will pan out. They are beyond our prediction horizon.

    Unfortunately we humans tend toward false precision. Gloss over enough details, and any research activity masquerades as development. And so we have Drexler for example writing down a timetable for molecular nanotechnology -- which any actual materials scientist (who understands the details and cannot sweep them aside) would see as hopelessly naive.

    Charlie's main point seems to be that human colonization of space -- even the space immediately nearby -- is still very squarely in the "research" bucket. (Although it's a logical error to draw a parallel to colonizing the Gobi desert; the reasons the latter isn't happening are entirely unrelated.) Nobody has yet written down a credible development plan for the colonization of space, a la Apollo in 1962. A corollary is that we have no idea when or whether colonization will: (a) actually become viable, and (b) occur. (When will we have room-temperature superconductivity?)

    The important question for us here on Earth in 2007 is: What research activities should we invest in today to maximize our chance of success, and how should we fund them? In contrast to its unmanned work -- largely driven by principal investigators outside the organization -- NASA's manned program strikes me as very poor from a research standpoint: Truthfully we learn next to nothing from projects like the ISS. I advocate that NASA spend more of its budget as a funding agency like the NSF, addressing the hard research problems: How to build self-contained self-sustaining ecosystems? How to build strong tether materials? How to make high-Isp rockets? How to do in-situ resource utilization most effectively? We have no idea where (or again, whether) the breakthroughs will occur, so as with any research activity we need to bet on several horses.


    DCortes @402: sorry to disappoint you, but David Gerrold (remember him? Tribbles? Hello?) got there about 20 years ago with his Chthorr series of novels.


    Typo: we need autonomous roots -> robots


    I think we shouldn't be too quick to sneer at the possible "magic wand". We haven't figured out all the laws of physics yet, and it'd be arrogant and short sighted to believe we have. Yes, the distances in space are mind-blowing, to say the least. But never say never. Imagine describing the modern day phenomenon of commercial air flights, television, robotic intrasolar probes, compact discs, cell phones, and the numerous medical advancements, to someone of the 16th century: you'd be spouting complete insane gibberish, and they'd either lock you up as a raving lunatic and throw away the key, or burn you at the stake for witchcraft. Since then however, we've discovered new properties of our universe and used them to our advantage: in short, we've discovered several "magic wands" over the past 200 years; who is to say we haven't still more to find ?
    Sure, in todays current situation, it looks nearly impossible, but todays technology will most likely not be tomorrow's technology. It's okay to dream. Just this week a new subatomic particle was discovered that is made up of all 3 diferent kinds of quark, for example. That's a first. We're still learning new things about the universe almost every day. ( )

    Lastly, to drive home the point, here are some other famous quotes from well-learned men of their era:

    • "Heavier-than-air flying machines are impossible." -- Lord Kelvin, president, Royal Society, 1895.
    • "Professor Goddard does not know the relation between action and reaction and the need to have something better than a vacuum against which to react. He seems to lack the basic knowledge ladled out daily in high schools." -- 1921 New York Times editorial about Robert Goddard's revolutionary rocket work.
    • "Everything that can be invented has been invented." -- Charles H. Duell, Commissioner, U.S. Office of Patents, 1899.

    and more at


    The most obvious answer for the problem of human colonization of the solar system (and beyond) is to change the definition of the word "human". I would suggest adding Ghost in the Shell: Stand Alone Complex to your Netflix Queue since it goes into this subject in great depth. Full body prosthetics would allow people to exist in the alien environment of Mars quite comfortably and for long periods of time.


    Mark @411, I'm thoroughly familiar with Ghost in the Shell. Trust me on this. (You really aren't familiar with my work, are you?)


    With all the talk about cost, it got me thinking that to make real progress Humanity will have to move away from money-based motivated society. Only then will the full utilization of the resources can take place.


    Dear Author:

    Evocative read. Thank you.

    Please learn to correctly use em dashes, en dashes, and hyphens. This is for the sake of your reader trying to figure out what you mean by "2-5" when you have several different scales going on. Do not use hyphens for ranges; use en dashes. Do not put space around an em dash.


    407: All I wanted was to invent a way to power interstellar ships! Now I have a death-ray named after me:

    Still, better a death-ray than nothing at all.

    I expect that my quotation is going to be what I am known for in a century, if I am known in a century, though.


    Jamie @395: With regard to Mars, Kim Stanley Robinson addresses the issue of the Martian atmospheric dynamics in his Mars books. A Martian atmosphere could be achieved, but that atmosphere has to be constantly created or it would bleed away over time. Personaly I think it's a waste of time to mess with planets when you can build big ships. Or hollow out asteroids and spin them (Greg Bear, Eon).



    hibernation, stasis or suspended animation could be a solution to the long travel time.

    But we should not forget the possibility of intelligent life. Even if we can observe the destination planet to a degree and can not see any signs of civilization (radiowaves/electric lights by night) it could be possible that once the ship is on route the aliens do develop their tech level and do not want any visitors.

    Imagine an alien society observing earth at around 1600 AD, they have a view of earth as if they are looking on it with human eyes from our moon, it looks similar to their own planet so they launch their generation ship with 10000 people in hibernation. 400 years later they arrive and find a planet with aliens capable of destroying the planet several times, that are in continues conflicts with each other for resources and that are intelligent enough to realize that the visitors have the technology, resources and motivation to build such a ship and that they do not have the energy to turn around and fly home because earth is not available to them.

    How would the United Nations Security Council handle this situation? Would they grant them some place to live? Would they nuke them? Would they lock them up to protect humanity and steal their tech?


    "I have reflected on this conversation over the years and realised that he saw me as some sort of pessimistic, defeatist, nihilist X-Generation figure."

    -- probably because you are. Individual 'mad' dreamers usually fail. Collectively they always win, and people like you always lose.


    I haven't the chance to read most of the posts here but managed to read far enough until they started repeating themselves many times. My 2 cents for the sake of throwing them in the kitty:

    Idealogically, I think space colonization should be a given for the same reasons we've colonized any awful place on this planet (awful here meaning any place not convenient to get to and back from). Historically speaking we'll make the attempt at least.

    Financially speaking ... well who can say. By today's standards, it certainly wouldn't make sense, but then again, having a space program past throwing satellites in orbit doesn't make sense ... financially. Yet we still have one, and it's growing (part of the reason point #1 should always be a given when speaking about human beings).

    Technologically: here's the rub ... if technology were not an issue, would this discussion be happening? I think most of us would agree, that it wouldn't be so far fetched to find a group of people willing to give up their lives here on Earth for a chance to start a new life on a distant planet. So in my mind, this discussion really boils down to a matter of when we'll be able to colonize and not if. Given our technological growth in the past 500 years, I think we might invent another "magic wand" or two in the next 500 ;)


    "But the ethical problem of superimposing Earth life over another planet's life would arise, as an intelligent species might arise if the planet was left alone (eg. some alien species could have decided to colonise Earth a billion years ago)."

    -- well, that wouldn't bother me. Blank treaty forms... gin... 8-).


    Martin T @417: identifying intelligent planet-bound life may actually be a lot harder if they're technologically advanced than if they're barbarians.

    Example: we are no longer blasting high-power TV signals at the stars, and our use of high-power ABM radar is diminishing -- because we've got more efficient tools. Climate change due to deforestation and warming is something that can be done with stone-age tools and fire, but it takes advanced technology to make the place look uninhabited and pristine. And as for looking for street lights from orbit, is it more efficient to light your streets ... or to tweak your genome so that your children can see in the dark?


    Thanks for the insight vis-a-vis the loss of other planet's gravitational affect/non affect on Earth in the event of their loss. I figured as much, but it's good to hear it from folks a lot more involved in the math than I am these days.

    A quick comment of this bit: But the ethical problem of superimposing Earth life over another planet's life would arise.

    LOL !!! When has this EVER been a problem???? If, as many seem to posit, the religious crowd will be on board (or perhaps a prime mover) in all this, don't you see how it then becomes our RESPONSIBILITY to enlighten these 'primitives' with the truth about Christ/God?

    The most likely mechanism for moving our species off this planet (some think it's how we got started) will be thru the dispersion of genetic or bacterial material. It's mass is not a problem, it's 'biological' stability is many magnitudes higher than the creatures/life it represents, and it won't mind being in a tin can for millennia.



    "Humans don't colonize places that don't already have people living in them."

    Funny how you mention that the Europeans colonized the Americas, and only because people were already living here. However, what exactly possessed the "native Americans" to cross the Siberian land bridge to come to and "colonize" the Americas in the first place. Realistically, the entire planet was colonized by humans and every in of it had no people living there to begin with.

    Sorry about this, I just got a little tired of this argument. I agree with a lot of the other posters here, and you can call it "foolish optimism" or anything else you want, but human nature is curiosity and exploration. I think that someday there will be undersea colonies just like there will be humans living in space.


    This is merely a "proof" from the perspective of current human knowledge. If everyone just believes this as the "gospel" truth, then no further progress will be made on knowledge. Major human progressions have come about when such seemingly infallible proofs have been disproved!


    "is it more efficient to light your streets ... or to tweak your genome so that your children can see in the dark?"

    Bingo. Or is it more efficient for the entire race to be digitized in a Matrix-esque utopia, and for 99% of the Earth to go back to it's natural cycle, and we only come out for vacation in a human or human equivilant body.


    Kurzweil's Children @425: I maintain that the Matrix is pants. It's entertaining noirish pants, but as a utopia it sucks and as extrapolation it's flawed.

    For a somewhat better take on the subject matter it might be worth grabbing a good book: "Diaspora", by Greg Egan.


    I couldn't disagree more.

    1) This makes no sense:

    "The future extinction of the human species cannot affect you if you are already dead: strictly speaking, it should be of no personal concern."

    It is perfectly possible to care about things that will happen after you die, otherwise why would anyone ever give their life for a cause they believe in? I sincerely want the human race to survive and prosper even if I'm not there to see it, as I'm sure do you if you take off your Machiavellian hat for a minute and remember that your life's work has been writing stories set in the far future (after you've died). Given the choice, do you really have no preference as to whether your books are all burned at your funeral, or retained for future generations to enjoy?

    2) You have failed to mention the most obvious and best reason for going into space again, namely that we will make fascinating technological and scientific discoveries in the process that will advance the cause of mankind as a whole. The original space race gave us all manner of amazing technologies, so what might the race to colonise Mars do for us? Cheap environmentally self-contained habitats could allow us to colonise inhospitable places on Earth; New types of engine and fuel could revolutionise Earth-based industries; Close-up study of other planets and their environments could yield a better understanding of our own. And who knows what fascinating discoveries we may make out there - maybe we will even find life.

    It may seem to you that there may be more pressing things to spend our money on, but dollar-for-dollar I doubt that there is any endeavour that would do more for the advancement of humanity than returning to space. It is an adventure that has the potential to unite the people of this planet and capture the imagination of the next generation in a way that no other project could.

    3) Remember how everyone wanted to be an astronaut when they were a kid? Remember how disappointed you were when you realised that you had no more hope of going into space than you do of becoming Prime Minister? Imagine if your children really could go into space - really could go and live on another planet. Imagine if you could make those dreams come true for the next generation in a way that our apathetic, cowardly, introverted parents just didn't have the guts or gumption to manage because they were too busy worrying about whether they should feel bad for having more nukes than Russia.

    Would that not be a worthwhile achievement? Or does my "appeal to sentimentality" fall on deaf ears?




    Hi , I'm an Alien from Planet Jadex, it s a far Planet in another Galaxy, I can give you more info on real Spatial issues. (+{~") = Peace,


    nick @427: again, like probably fifty or a hundred folks who've commented so far, you're confusing space exploration and space colonization. I'm bored. At least try to review the earlier comments and find something original before you post here?


    Re (dcortesi, #402): "but if you do here's your reward: a really good story idea!"

    Wow. Charlie, do you get this a lot? That must get so annoying if you do.

    News flash to #402: Ideas are a dime a dozen. It's the implementation that matters -- all of the hard work to turn it from a good idea to something people will care to read. If you think you have a great idea, first make sure that it hasn't been done to death, then put forward all of the hard work to make it happen.

    Re (Charlie Stross, #377): "space elevators are one of the key non-magic (but non-trivial) technologies that undermine the argument that space colonization isn't viable."

    I disagree. I don't think space elevators really have that potential. The strongest SWNT that's been measured thusfar had a tensile strength of just over 60GPa. Despite the crazy predictions early on in the science of 100-120 GPa, it is becoming more and more conclusive that they just aren't that strong. Here's a paper on a modern model, showing 50-60 GPa.

    The problem is, the "realistic" space elevator plans call for SWNTs of 100-120 GPa tensile strength. With numbers of 50-60 GPa, the required taper factor means an elevator that's simply too massive to launch to justify such a small payload capacity.

    But it gets worse. These are the strengths of individual tubes; that's the upper bound. Nanotubes naturally form into "ropes". The strongest ropes measured thusfar are only a few GPa; here's a paper that describes 3.6 GPa ropes. Even if it can be improved (say, by longer tubes, or pressure-induced crosslinks that trade SP2s for SP3s at the cost of some tensile strength), it's never going to reach, and probably not even near, the maximum strength of the individual tubes.

    It gets worse still, though. That's for individual ropes. You still have to make bulk cable out of the ropes. If you lucky, you can near but not reach the strength of the individual ropes.

    That's not the only factor still; you have to then be able to do all of this affordably. I think that the laws of physics dictate that we're looking at, at best, something like 30-40 GPa for the cable.

    Those just aren't realistic numbers to be working with. Yet, we're up against the limits of covalent bond strengths when it comes to nanotubes.


    "is it more efficient to light your streets ... or to tweak your genome so that your children can see in the dark?"

    your right.

    another question

    "is it more efficient to preserve your home planet ... or to exploit it and than leave it so that your descendants can live on another planet in another solar system (if they survive the trip and the arrival)?"

    without FTL interstellar travel lacks any motivation to do it except an immediate supernova. Sure their is a chance that the planet could be hit by a planet killer asteroid, but then leave for mars and come back after some years/decades.


    Cost-benefit analysis is rational and sane, and you've made a good case that colonization fails.

    Humans are not, however, entirely rational or sane. As it happens, I believe my God (who's altar may be a coffee machine) has commanded me to "go forth". The question, then, is whether or not I (and/or other like-minded individuals) have the resources and will to do these things. Allen, Bezos, Carmack, Musk, Bigelow and Branson all seem to be heading that way. The threshold for doing so is coming down.

    It doesn't matter if the reasons are "worthy of airtime". What matters is that reasons and resources combine. For that, it's just a matter of time.


    A large accelerator could be built in Earth's orbit to propel the ship to speed. It could be solar/nuclear powered. 30,000,000 m/s? It would only take 85 hours at 10 G's!


    "For a somewhat better take on the subject matter it might be worth grabbing a good book: "Diaspora", by Greg Egan."

    Thank you sincerely. I just read a summary of this at

    I've spent the last six months of my life after seeing "Cosmos" by C. Sagan on Science channel last winter, devouring every book on cosmology, particle physics, etc. (I'm an EE by education). Just this week I read his "Candle in the dark" and Kip Thornes "Einsteins Legacy". I've been craving real thinking like this website and brave SF like "Diaspora". I can't thank you enough. - Shane in Oklahoma


    I could kind of see where the author (or any sci-fi author) might feel frustrated with trying to come up with a plausible or near-plausible tale of how space colonization (especially of another star system) might realistically happen without having to rely on a "magic wand(s)".


    421: This overlooks the fact that our technology allows use to send deliberate messages to a large fraction of the galaxy and that the cost to do this is declining. I mean, Daily Planet did it as a promotional gimmick in 2005.


    All the technological objections I've read here are mere quibbles and can be overcome or sidestepped.

    The REAL problem with space colonization is whether the colonists can be counted on to leave the Mother Planet alone. Imagine a fanatic, "Jim Jones" type sect with scads of money and scientists that decides to leave Earth and colonize [fill in the blank]. They don't want interference from the "nonbelievers" later on so as they leave Earth orbit, however, they drop plague bombs.

    As long as Earth is the only possible place to live the nutcases have a vested interest in not doing something like this. Only the most criminally insane would even consider it and they are an extremely small minority. Space colonization adds millions more less-exremely crazy but still nutso types we have to keep a lid on. I don't think it's a manageable problem.


    Regarding the "eggs in one basket" argument and "what's the benfit to us?" ...

    I'd suggest it is a straightforward extrapolation along the lines of "I care for my son, I will care for the grandchildren he will hopefully give me some day", and it is no great stretch in the abstract to "care" about great-grandchildren I may or may not be around to meet some day. And so on...

    I think you are being deliberately contrary on this one point -- in spite of the fact I think you raise many other great points.


    I agree with Mr. Stross about electromagnetic tethers. I agree that there must be 50 ways to leave the planet, which are NOT rockets. We can't tell which will actually make it out of the valley of the shadow of death (in the Venture Capital sense). I think some will. I also thing that there will be New Physics and New Biology. But the Stross essay, intentionally, does NOT count any such unhatched chickens.

    Interesting to me that all 4 tribes of Relativity True Believers, Relativity-skeptics, Evolution True Believers and Evolution skeptics have commented. Einstein was God. Einstein was the Devil. Darwin was God. Darwin was the Devil. Mr. Stross pushed more buttons than I first noticed.

    As a scientist/science fiction author, I share some of the Stross schizoid position: simultaneously be able to operate professionally within the paradigm (don't forget, DNA-obsessives, that he has a degree in Pharmacology), and be able to see the anomalies that will bring the paradigm crashing down, while extrapolating atmospherically some aspects of the nascent new paradigm.

    I don't care about universes with no matter nor energy, albeit I acknowledge that Einstein thought deeply about what Mach said about these, and that the Math is easier for them. I care about the cosmos that I'm in, which certainly does not follow Special Relativity [hint: wheels rotate], and pretends to follow General Relativty (in one isotope or another) over a broad range of length-scales, but not all the way down.

    Establishment claims that only 4% of the mass of the cosmos is in the old stuff (matter and energy) that we learned in school. 23% "dark matter"; 73% "dark energy." Oh yeah?

    There is a paradigm smashing paper in the current issue of Science, about the ENCODE project.

    Bottom line: in the Human Genome at least (and other projects show that this applies to Drosophila melanogaster as well), there are (for the most part) NO SUCH THINGS AS GENES.

    The word is still used, with a mass of epicycles encrusted onto the concept so that it takes a grad school semester to even define "gene" any more.

    But just as we don't know what hold the galaxy together (i.e. the epicycle "dark matter") we don't know what holds the genome together (i.e. the epicycle "heterochromatin").

    The model that came from Morgan et al at Caltech in the 1930s was: one gene, one enzyme.

    That is, the chromosome is mostly DNA, and certain substrings of the DNA code for proteins. They evolve by Natural Selection. Some other parts regulate. The rest is non-functional, noise, or junk, or outside the paradigm, and never gets transcribed to RNA nor has function nor is selected.

    The actual DATA using the latest methodologies in combination, applied to 1% of the human genomne, partly bits we know, partly bits chosen at random, is, to the contrary:

    2% to 4% is crudely akin the "genes" and "pseudogenes." More than half is functional, more than half ends up copied to RNA, the RNA has some dynamic interaction with other RNA and protein in ways we don't know, much of the functional stuff (once called genes) are selectively neutral (or only very weakly subject to natural selection). Things we don't understand are sometimes evolving by natural selection. Functional things are sometimes not strongly conserved. Strongly conserved things are sometimes not functional. There is large-scale structure correlated with when in the reproductive cycle the cell is. The performers formerly known as genes are broken into pieces, scattered, scrambled, started and stopped by things far away on the chromosome in both directions, and overlapping.

    There is no "vacuum." There is no "gene." The words do more harm than good.

    The truth is out there.

    -- Prof. Jonathan Vos Post


    Though I've probably said enough, I'd just like to reinforce point 2) by re-wording the following paragraph:

    "Now, these problems are subject to a variety of approaches — including medical ones: does it matter if cosmic radiation causes long-term cumulative radiation exposure leading to cancers if we have advanced side-effect-free cancer treatments? " ... " But even so, when you get down to it, there's not really any economically viable activity on the horizon for people to engage in that would require them to settle on a planet or asteroid and live there for the rest of their lives"

    which basically amounts to saying

    "In the course of getting into space we might be inclined to invest enough money into medical research to finally cure cancer once and for all as a means to get around the cosmic radiation problem. But I hardly see any economically viable reason to justify all this effort."

    I'm gob-smacked that you can consider curing cancer as just another example of wasted effort that would make the whole project less worthwhile. If anything this tells me that even a failed attempt to go into space again might well yield sufficient technological benefits to make the whole thing worthwhile.


    433: Let us take the wire brush of simple calculations to the foreskin of that idea, shall we?

    30,000,000 meters/second at 10 gees takes 300,000 seconds.

    S = 1/2at^2, S is distance (please donate to fight the scourge of really bad spelling amongst physicists), a is acceleration and t is time. In this case, a = 100 m/s/s and t = 300,000 seconds. S must therefore be 4.5x10^12 meters or about 30 times the distance between the Earth and the Sun.


    The time scale of life on earth is three billion years and in that scale the movement around the stars is possible. nano technology will be the next great leap and you will find the distances counter intuitively srink again. Your writtings are good motovations to get matters soughted out on earth. Al Gore has his environmental party on 070707 or 7 July 2007. Roddy


    Jack @408: Is the issue that colonization of space is currently technically infeasible or that it is enormously impractical from an economic stand point. It seems that Charlie's thesis is arguing the later, that none of the FORESEEABLE technological improvements would make space habitation cost effective.

    427: Arguments for "there is so much to learn" while true show great bias because one could argue that there are plenty of terrestrial issues that are largely unknown and unexplored and could be studied for equal or greater benefit at a fraction of the cost. Non-terrestrial issues could be studied remotely by robot with little risk, at a fraction of the cost, and with far fewer complications than sending people.

    "Eggs in one basket" motivations while valid concerns with an emotional appeal don't take into account the enormous costs involved. One might argue that the effort itself may be so costly as to destroy civilization since it draws resources away from immediate concerns from the environment. And the success of any such effort would be highly doubtful. Barring an "imminent and unavoidable" catastrophe I can not imagine humanity making the investment given all the other considerations. At least not given the current costs/time involved.

    Its not just a question of whether colonizing other worlds is a noble effort, its that it is a very expensive option of a number of very noble efforts.


    Von Post @ 438:

    "I agree with Mr. Stross about electromagnetic tethers. I agree that there must be 50 ways to leave the planet, which are NOT rockets. We can't tell which will actually make it out of the valley of the shadow of death (in the Venture Capital sense). I think some will. I also thing that there will be New Physics and New Biology. But the Stross essay, intentionally, does NOT count any such unhatched chickens."

    I don't think you could have this discussion intelligently without counting on "some unhatched chickens". Even Mr. Stross admits to playing fairly fast and loose with most of his initial assumptions at trying to hypothesize a real world example of how we might go about colonizing space. Otherwise if you go by the "here and now" then obviously space colonization isn't feasible.

    Otherwise Mr. Stross would be writing sci-fact and not sci-fi ;)

    P.S. - remind me to never use the word "gene" around you. I got blisters thumbing through my reference material that much.


    Charlie @427:

    "again, like probably fifty or a hundred folks who've commented so far, you're confusing space exploration and space colonization. I'm bored. At least try to review the earlier comments and find something original before you post here?"

    I apologise for boring you, but if you find reading 420-odd comments on your own article boring then you can hardly expect me to read them all.

    To address your point though, I don't feel that the distinction between space exploration and space colonisation (or even colonization) matter much in this debate. Lets simplify the argument by removing the nouns.

    You are saying "Whilst we should invest in X, it's not worth attempting Y because it is harder and will require us to spend more on advancing technology"

    I am saying "But it is precisely because Y is harder and will require more advances in technology that it is worth doing."

    Your argument would no doubt have applied equally well if X was "putting a chimp into orbit" and Y was "going to the moon", and in that case too you would have been wrong.


    Regarding "'Eggs in one basket' motivations while valid concerns with an emotional appeal don't take into account the enormous costs involved."

    To which I say OF COURSE they don't affect the difficulties -- but Charles was trying to dismiss the motivation itself as motivation.


    Charlie @ 377; One of life's minor joys is being a pragmatic realist working for a company full of pragmatic realists who determined - if it's possible - to do interesting things.


    Charlie @ 377; One of life's minor joys is being a pragmatic realist working for a company full of pragmatic realists who determined - if it's possible - to do interesting things.


    I say slow migration is the key. A few hundred years to colonize the moon. 500 more to build cities on Mars. 1,000 years to finish up Jupiter's moons. 5,000 years to move beyond. By the time we hit 10,000 years, we still won't be able to go directly from a plant light years away to Earth. However, we can take short diistance trips in between each body we've built on with it's induvidual societies. (Keep in mind, most people today still never travel more than 50 miles outside of their place of birth in their entire lifetime) There's no real rush to colonize all of these bodies. And when you think about it in relative terms, 10,000 years is a drop in the bucket to do all of this. I'd also like to believe that humans will probably shed there biological bodies and upload their conscienceness into self-repairing centarian super robots. Or we can dispatch some sort of colonizing some sort of AI army to do all of the groundwork (sidewalks, toilet installations, Startbucks) on these worlds. Stick a few hundred cloning machines onboard a couple of thousand probes and there you go.


    @402 - it's been done - and done well - by David Gerrold in his 'War of the Chtorr' series.

    In that one the first thing that people notice is a plague that kills 9/10 of humanity, with a post-plague population crash. Then things take a turn for the worse ..

    Of course he's not finished the last novel yet so it may all end in tears. Always room for a better treatment of the idea.


    Nick @440: curing cancer isn't going to happen as a side-effect of a space program (indeed, as one of those "trivial details" which some folks appear to be dismissing all objections as) -- it's going to be a separate medical project, and as important -- if not more so -- than the development of antibiotics in the 1930s through 1950s.

    But we're not going to invest money in cancer reseach so we can send astronauts to Jupiter orbit. More likely, successful cancer research will suddenly demolish one major obstacle to sending astronauts to Jupiter.

    There's a major causality problem at work here: NASAs 1960s funding propaganda ("look! We wanted to go to the moon so we invented velcro! And Tang! And the Fisher space pen!" -- all of it half-truths and lies) seems to have convinced a lot of people that aerospace engineering brings through huge technical breakthroughs and lots of lifestyle enhancements for the rest of us.

    I'll tell you what kind of lifestyle enhancements I enjoy from the space program: the knowledge that 3-day weather forecasts are usually accurate. (That's a gigantic life-saver.) The ability to know to within centimetres exactly where I am at any time, and to know to within milliseconds what that time is. (Thank you, GPS.) The expectation that I can phone someone on the other side of the world for only about ten times what it costs to phone someone on the other side of the city. All of these are good and necessary and profitable applications of space technology.

    But unless I'm very much mistaken, we've yet got to see any significant medical breakthroughs coming out of space tech, for much the same reason that we don't expect breakthroughs in space exploration to come from the haut couture fashion industry: they're in the wrong field.

    Karen @430, you may well be right about the limits of covalent bonds. On the other hand, space elevators may be useful elsewhere in the solar system -- on the Moon, or Mars, where the support weight is much, much lower than on Earth. And I see no obvious reason why lower-tensile strength fullerene ropes wouldn't be an excellent material for building a Momentum-Exchange/Electrodynamic-Reboost system. Tethers are less elegant and have a lower payload capacity than a true space elevator, but don't require magic materials, self-powered or beam-powered climbers (just a sub-orbital launch stage able to rendezvous with the lower end of the tether -- difficult, but not outrageously so: it's analogous to performing an in-flight refueling maneuver at apogee of a ballistic trajectory), sidestep the Van Allen belt transit problem, and could show a quick route to profitability. And I suspect it's also possible that we'll see a commercial one built within the next 20 years.

    A combination of reusable sub-orbital vehicles descended from Scaled Composites' Space Ship One, feeding payloads to an MXER tether system for insertion into LEO, could well give us a launch capability nearly as cheap as a true space elevator. And I'm willing to be cautiously optimistic about that.


    Hi All -

    Just bored, sitting in my cubicle when I slashdot across this.

    Anyone ever think that maybe Earth IS the form of travel that you're envisoning? That maybe someone / something / some population such as ourselves (I know Earth's old but have no clue HOW old) Billions of years ago had this same conversation --

    and EARTH is the means of transportation?

    If I'm way off, I'm sure you'll tell me why... but the expansion of the galaxy and all the moving parts...

    Do we know where Earth is ultimately headed / what crosses its ultimate path?

    I mean no offense to anyone reading this -- I think it's a mass collection of everyone's thoughts on the future, a very enjoyable read, and I hope at least one of us is right :)


    @452: I would think that would be analogous to throwing a beach ball in the ocean, with the idea that the current is going to take it across the world.

    A neat trick to try but I'd hate to think the Human species is someone else's "message in a bottle".

    Call it the Human elitist in me ;)


    Wow, I was reading the article and surprised that it would take 5 days of the total power production of the earth to get one man to the nearest star. I figured it would take much more.

    Now having said that I think the solution to interstellar travel is point (a) "outrageous amounts of cheap energy" which is abundantly available (E=mc^2) just not very accessible. After all the mass reduction in most nuclear reactions is a very small percentage and they tend to produce huge amounts of energy. It might take your equivalent of a magic wand to tap some more of that energy, but it's there. I think the larger question is whether tool using intelligent beings are a stable outcome of whatever mathematics governs the process of evolution, and I don't believe there is evidence either way yet.


    A neat trick to try but I'd hate to think the Human species is someone else's "message in a bottle".

    By that rationale why not take it a step further back and envision that a truly efficient "creator" type said "Hm, all I have to do is create a really violent transition of a high energy state to a low energy state, and given billions of years that (relatively) low energy state (matter) will spontaneously self assemble into A) Self awareness and then B) evolve into a singularity of ultimate knowledge.

    Maybe that's how Gods procreate.

    Ultimate efficiency and effectiveness.


    First off, I really enjoyed the article. I do however, have one complaint.

    If 1AU = 1CM shouldn't that imply that you stick to the metric system instead of switching between that and the EST? "it takes us 2-5 years to travel two inches"

    Ok... but we're dealing in the metric system.... (CMs). Sure, the conversion is possible but since the whole basis of the article is to give the reader an idea of how impractical it will to travel between star systems by using a scaled down model in units everyone is familiar with.

    Granted this is a nerd-centered audience that will read this article but the lack of consistency does hurt.


    Matt @456; I'm a metric bunny from the UK, and I'm of the last generation who remember inches and stuff -- I'm effectively bilingual in units, up to a point -- but I used inches and miles as a concession to my mostly-American readers.

    There's no point dangling a metaphor in front of someone if the reference point you use is one they don't understand.


    Re 444 (the number of days, BTW, that the "students" held American captive in Tehran).

    This thread IS mostly about space (including between people's ears) but the Biology has been acknowledged important (immortality, closed cycle ecological support systems, hibernation, control of human evolution), so, to save you hitting too many Bio reference books:

    I exaggerate for rhetorical reasons, but this really is revolutionary work I'm reading.

    In the sense of Mendel, there are such things as mathematical rules about discrete units of inheritance. But the last straightforward link to DNA is broken.

    To recaptiulate (with vast oversimplification) the epic historical fiction of the key concept [reference Nature, 25 May 2006, p.400]:

    1860s: Gregor Mendel, Austrian monk, plays with pea plants, fudges data, publishes in most obscure place (slowing down recognition): basic rules of inheritance defined; traits determined by deterministic units passed from one generation to the next, God knows how.

    1909: Wilhelm Johanssen, Danish botanist, coins word "gene" for the unit associated with an inherited trait, admitting that the physical basis is unknown.

    1930: Thomas Morgan (enjoying the monastic atmosphere of Caltech) analyzes why time flies like an arrow but fruit flies like a banana, and concludes that genes sit on chromosomes, an idea popularized as beads on strings. Turns out as accurate as image of atoms being electron planets orbiting nuclei.

    1941: George Beadle and Edward Tatum launch the model that one gene makes one enzyme. The classical enzymology yields a PhD for Isaac Asimov, and by 1977 (when seen through the not-yet-named fields of Artificial Life and Nanotechnology) a neither granted nor denied PhD for Jonathan Vos Post [middle name from my Mom] though all key equations later published in refereed journals and international proceedings.

    1944: "What is Life?" nonfiction book adapted from blog (I mean lecture series) by Erwin Schrödinger. Francis Crick later cited "What is Life?" as the best theoretical description, before the actual discovery of DNA, of how genetic storage would work. In the book, Schrödinger introduced the idea of an "aperiodic crystal" that contained genetic information in its configuration of covalent chemical bonds.

    1944: Oswald Avery, Colin Macleod, and Maclyn McCarty show that genes are made of DNA. This raises more questions than it answers.

    1953: James Watson and Francis Crick find the golden spiral stairway to heaven, publishing the structure of DNA in a sneaky race against Pauling (they ply Pauling, Jr., with sherry to find out what Linus, Sr., is up to) and denying the essential contribution of Rosalyn Franklin and Wilkins and others; the central dogma of molecular biology comes from this: information flows from DNA to RNA to protein. That's all ye need to know.

    1970: Reverse transcriptase was discovered by Howard Temin at the University of Wisconsin-Madison, and independently by David Baltimore, who later is Caltech President. Information can flow from RNA to DNA, against Dogma, and crucial to AIDS.

    1977: Richard Roberts and Philip Sharp discover that genes can be split into segments, leading to the idea that one gene can make several proteins.

    1993: The first microRNA is identified in the worm Caenorhabditis elegans; the worm turns.

    2003: GeneSweep: Human geneticists yell at each other late into the night, hammering a compromise definition of protein-coding genes, in order to decide who won the bet on the number of human genes. The winner is announced, but the consensus is that we have no idea what the real answer is. ["gene = locatable region of genomic sequence, corresponding to a unit of inheritance, which is associated with regulatory regions, transcribed regions and/or other functional sequence regions."]. Yeah, right.

    2006: the paradigm begins to emerge that human genes are one long continuum.

    2007: ENCODE supports the new paradigm much more than the old.

    2008: Charles Stross publishes the key book combining new paradigms of physics and biology, later winning him a Nobel prize, and cited by Eschaton as the best theoretical description, before the actual discovery of XYZ, of how galactic colonization would work.


    @455: Wow and I dared to call myself a Human elitist! Haha ... well I can't say to know but I'm not going to venture so far as to say any space colonization we do are a part or in whole tied to exostential creationism.

    But then again given enough time, who knows?! However I would say that colonization is the key to longevity of a species on a cosmic scale (back to that whole "eggs in one basket" debate).


    Post 439: To be fair the term "gene" has been debated heatedly for decades due to its vagueness. The ENCODE paper is just the latest in a long line of papers showing that a gene is not associated with a precise location in the genome. Nonetheless, the term, fuzzy as it may be, is still quite useful.

    Much like Newtonian physics, straight forward descriptions do not capture all the details but work perfectly well in day to day life. There are more precise more all encompassing but less practical theories that have their place like general relativity or quantum physics.


    @458: And this applies to the conversation .... ?


    one could argue that there are plenty of terrestrial issues that are largely unknown and unexplored and could be studied for equal or greater benefit at a fraction of the cost.

    Sorry Doug, but seeing how we've spent our money so poorly here on Earth, I'm all for more funding to space exploration. Rather see a moonbase than another 'military intervention' in Iraq. To quote a song from Bad Religion "10 million dollars on a losing campaign / 20 million starving and writhing in pain /big strong people unwilling to give / small in vision and perspective"

    Two quick points. 1) One large asteroid could provide vast metallic resources. Same for a chunk of water-ice from, for example, Saturn's rings. Or methane from any of the outer planets. Once we acquire these resources, they're free for industrial manipulation in a zero-g environment where we don't have to worry about polluting Earth's biosphere. And as we have seen with every major war, and the birth of the aerospace industry - the technological development driven by a space-oriented industry spills over into the consumer sector. Space tech doesn't stay in 'space' long, it finds its way into the home. Essentially, the economic costs of aerospace development over the last 40 years have paid for themselves, and will continue to pay indirectly.

    2) Surprised no one yet has mentioned a space elevator, which - while initially expensive to construct and marginally costly to maintain - would lower the cost-to-weight ratio of putting payloads into orbit by several orders of magnitude and provide a quick way to transport goods and services to and from orbit. Considerable research has been

    I've heard rumors of photon pressure launch devices (big lasers) that were shut down as 'anti-satellite weaponry'. Let's not forget the ill-fated 'Project Orion' of the 60s using nukes to blast giant steel plates into orbit.

    Anyone remember all the attempted debunking of powered flight, before the Wright Brothers? The energy expenditure to keep heavier-than-air objects in the sky was once considered ridiculous. With the discovery and implementation of the airfoil - a simple, inexpensive invention - the entire globe was opened to travel. This essay reminds me of those nay-sayers.

    Just because we don't know how to solve our problems doesn't mean they're unsolvable. Our ignorance shouldn't prevent us from trying, and it seems that's what you're advocating here.


    Charlie@451: I agree completely in the general case (although I'm not a big fan of SS1's unscalable design, nor its one-near-disaster-per-powered-flight track record in its testing phase ;) ).

    In my view, the main issue with other uses of tethers, such as rotavators, will be economics. For example, assuming that the technical challenges of such a system can be overcome, said tethers will need to be able to overcome aerodynamic drag across the many miles of their length, which means a great amount of electrical power spent on reboost compared to the amount of payload. Getting that sort of power generation capacity in orbit isn't a trivial capital cost that must be amortized. I could crunch the numbers if there was interest.

    At this point, who knows how the economics will work out, but I don't expect any miraculous numbers to come from it. Better than our current, obscenely high prices per kilogram? Probably. But there are many burgeoning techs that can also provide us better numbers. Scramjets. Unusual launch mechanisms (ground-fueled tow launch, midair-fueled tow launch, midair docking for fueling, captive carry/fuselage underside, captive carry/fuelage top, captive carry/wing, and even captive carry/internal stowing). Nuclear thermal rockets. Advanced reusables. Even optimized disposables (see SpaceX's Falcon series for an example). When it comes to rocketry, fuel is the cheap part. It's all of the labor that's expensive. If modern history has shown us one thing, it's that technology has great potential to reduce the amount of labor needed to accomplish a task.

    I think an author could be justified in using any such methods for spaceflight in their futures; at this point, it's too hard to say what the real future will hold. On the other hand, I don't think it's justified to make the price per kilo reduction too extreme. Likewise, given the amount of industrial infrastructure needed to allow for sustainable, largely independent life on another planet, I don't think that true colonization (interstellar or intrastellar) is realistic in the foreseeable future.


    Thanks for the great article! It's nice to actually see someone put numbers to my thoughts for a long time. In particular I've always had the perspective that before colonizing other planets it would be an order of magnitude easier and cheaper to colonizing undersea or underground, before colonizing underground it would be an order of magnitude easier to colonize the arctic/extreme desert.

    Earth-orbiting space tourism, as you point out, has the potential to become econonomically feasible within my lifetime (hopefully another 50 years or more!), and robotic exploration of the solar system is proceeding apace.

    Anything beyond that, well, we're talking on the order of centuries. I'm faintly optimistic that some "magic wand" transportation technology might someday be discovered, only as there are still so many mysteries as to how space and time fit together. Should give us plenty of time to get our act together or kill each other off.


    By the way -- you've created a monster with this post. ;)


    @ 462: 2) Surprised no one yet has mentioned a space elevator

    You know, just doing a simple search for the phrase "space elevator" on this page would show you that: a) Charlie mentioned the concept several times in his original essay, and even linked to a Wikipedia article; and b) it's shown up in about 20 comments so far, including some moderately detailed arguments about whether materials with the necessary tensile stregth are actually plausible.

    Just suggesting that anyone finds themselves thinking, "Hey, no one has mentioned X!" -- well, check and make sure. At this point, it's very likely someone has, including Charlie himself.


    To some: Charlie's article is a good one. Many posts here are also good. However, if you are not contributing to the discussion by presenting arguments, please show some constraint. Don't insult, or mock spelling errors. If you have a point to make, go for it, otherwise, please bear in mind that this is a LONG thread now.

    To Charlie and all: I've presented here my arguments about History showing us how wrong we are and how little we know at any given century. I've also expressed my belief that there will be some magic wands (we won't know which untill they arrive though). I did this, based on the principle that if it happens once, it can happen again. And again. It has been like that forever. But I won't linger in this point. I will go on to the Economy issue. Charlie says it doesn't make sense to spend that many resources to achive interstellar travel. Well, he is right again, in the same way he was wrong before (pun intended). It doesn't make sense to you or to me. But again, you are applying today's knowledge to future needs. I'll explain what I mean. As you might have noticed on my previous post, I am an History man, so here I go taking us back in to the past for a glimpse of the future: Charlie talks about the Gobi Desert and the North Atlantic and how we won't colonize that. He is a bit right and mostly wrong. We have oil rigs in the North Atlantic. And there is human life there. Not much, but there nonetheless. The Middle East deserts are a better example of the point I'm trying to make: 19th century: Sand. Camels. Desert. A handfull of travellers twice every year. 21st centry: Du-freaking-bai.

    Yes, a completely useless resource at the time (oil), transformed deserts into luxuriant human habitats. Millions of people are not something to disregard. Oil is so vital to us now that I don't need to explain the consequences to our society if it was taken from us. It was as useless as asteroids a couple of centuries back.

    So, right now, going to the other stars, or spending money in such efforts is as stupid as buying land in Dubai two centuries ago.

    I'm not saying that we will colonize the most stupid and idiotic place on Earth or Space. I'm not saying we will exist as a species in the Year 5000 and/or achieve star-travel. But I am saying we might.

    I'm not going with the idealistic movements out there. My religious (lack of) belief does not weigh here (keep religion out of every discussion, allways). I am talking about facts. It's happened before. Lots of times. It might happen again. Once. Twice. Ten thousand times. Who knows? Not me, not you, and specially not people who underestimate History.


    Justin @462: space elevators have been discussed extensively here. You might want to search the comments (especially for "elevator" and "fuller" (as in "fullerene")).

    We're nowhere near being able to build an actual photon-pressure propulsion system -- it takes about 3 gigajoules to provide one newton of thrust (i.e. the output of three large nuclear power plants -- converted into laser light at 100% efficiency) to balance a 100 gram, or three and a half ounce, paperweight against Earth's surface gravity. And the heat dissipation issues are ... special.

    There have been successful early tests of using lasers to flash-heat air (or other reaction mass) under a lifting vehicle. But effectively you're just replacing a rocket (with high-energy fuel and oxidant) with a rocket (with inert fuel and an external energy source).

    Nissl @464: I'd like the space tourism thing to happen. (I'd like to hope that it gets cheap enough that my wife and I can enjoy a second honeymoon in free fall while we're still young enough to enjoy it. But as I'm 42 and not in brilliant medical condition, I'm not optimistic ...)


    Long before we manage do get such spaceship together, will we have to manage our earth as a spaceship... This challenge will be the mother of all challenges, and failure to do so will bring our end.

    Judging by the current trend of human development, the probability of reaching an era where the proper technology exists is very low, as we will probably have "self destructed" long before. Pretty much the same way the Khmers did around 14th century (IIRC), by ruining their environment.


    One more point - if we did reach the point at which we could colonize the moon or mars, why not just build a colony in space? You're going to have the exact same concerns regarding a sustainable sealed environment in either case. All that Mars gets you is 1/3 of earth's gravity, at the cost of dealing with a gravity well. At least with a rotating colony you can set the gravity as you please.

    Now if our distant descendants did become fantastically rich enough to build enormous, self-sustaining space colonies despite the economic pressure against doing so, they might well nudge them in the direction of a habitable star. Hmmm...


    They've repeatedly mentioned space elevators in the previous replies.

    "Just because we don't know how to solve our problems doesn't mean they're unsolvable"

    We're asking the questions incorrectly.

    In Robert T. Kiyosaki�s book "Rich Dad, Poor Dad" he says something to the effect of "People always tell me "That's impossible, you can't make money doing that here, it won't work because of XYZ." They rarely say "How can I make money doing that here."

    We need to ask "How can we colonize these planets?" "How can we ensure our survival?"

    I work as a design engineer for a communications company, putting in state of the art comm and computer systems in small rural schools in Oklahoma. I'm doing everything I can to make a real change in how we as a society educate our children in technology. Our designs move schools to a centrally managed terminal server network/comm topology instead of the failed PC centric topology that is currently in use. We're getting rid of the overworked, unqualified gym coach trying to double as a sys admin/computer tech and managing all systems centrally offsite. In the schools we've done so far you wouldn't believe the difference when kids sit down to fast, clean, effective computers, vs. the bullshit, clapped out, barely running systems they were using. Since we centrally manage them I get to put shortcuts to websites that inspire wonder about the universe, and science, and places where they can think. The world needs to spawn more Carl Sagans, Ptolemy, Leeuwenhoek, Hypatias. Equally as important they need to understand why Stalins, J. Robert Oppenheimers, etc are to be eyed skeptically. When they find out how much amazing stuff there is in the real world, their questions and sense of wonder is inspiring. Maybe we can turn up this signal and dim the background noise of Paris Hilton/American Idol/other mental bubblegum (lots of chewing, no nutrition). Maybe the guy that invents viable space travel, or how about trans m-brane travel is right now a 9yr old redneck Okie from Muskogee.


    Nissl @470: again, read the bloody comments. We've chewed that one to death already.

    Karen @465: you're right :)

    ... This essay ran to 4000 words; the ensuing thread, at 82,000 words (including the essay) would make a 250 page book.


    Kurzweil's Children, #456: "Maybe that's how Gods procreate."

    See James Tiptree, Jr., "A Momentary Taste of Being".


    Of course prospects based upon today's technology don't look so good. The flaw in the reasoning of this post is that you're not accounting for the fact that technological progress is exponential. Just as so many others have blindly imagined future progress based upon work with tools of their own day, your argument is far too myopic.

    Nearly everyone thought Kurzweil was nuts in the 80's when he started predicting that a computer AI would defeat the world chess champion before the end of the millennium. As it turned out, Kurzweil nailed the prediction, and Deep Blue beat Kasparov 9 months before Kurzweil's predicted date. Similarly, the less visionary among us thought he was bat-shit insane about his optimism at the beginning of the 15 year-long Human Genome Project. Not only did the project reach completion within the allotted time, but Celera (an independent company) did it first!

    Do you really want to bet against exponential progress? Robinson's Mars trilogy greatly underestimates advances in biotechnology and nanotechnology.


    "I think the Fermi Paradox puts a great big nail in the coffin of interstellar civilization. Given the age of the Milky Way, we should have been visited and colonized by the representatives of at least one alien civilization by now. The fact we haven't tells us that either:

    1) Interstellar colonization is technically impractical or impossible, regardless of your advancement 2) Interstellar colonization is possible and perhaps even practical, but nobody with the ability to do it bothers because there are better ways to spend your time and energy once you have technology that advanced 3) Civilizations never acquire the ability to colonize the stars because they're wiped out by their advanced technology, via wars, accidents, runaway AI or other processes

    There are other possibilities as well (like interstellar exterminators, who go around snuffing out technological civilizations to prevent them from spreading), but they all seem far less likely.

    I'm betting on option 2, but 1 and 3 wouldn't surprise me."

    I really got a kick out of this one and had to reply.

    Maybe we have been visited by one of these alien civilizations. Maybe they are keeping tabs on us right now. Maybe they came took one look at us and decided we were too boring to bother with. The fact that we haven't been visited by ET does not mean they aren't out there, nor does it mean that interstellar travel is impossible. What it does mean is that WE haven't been in contact with them in a reliable and accepted manner, and nothing more than that.

    I believe that there is other life in the universe, and maybe we have had extraterrestrial visitors, maybe not. The one thing I'm sure of is just because the general populace of our little planet doesn't converse with ET on a regular basis doesn't negate the feasibility of interstellar travel.


    From 453:

    and EARTH is the means of transportation?

    Absolutely, but I hadn't put quite the angle on it you are suggesting. My thoughts on this didn't make the previous posts I have in this thread, but here for the mix is my take:

    Suppose we had the unlimited cheap power (proposed as necessary for nearly all these solutions). Would we then not also have the means to just use the Earth itself as a giant spaceship? Of course we'd have to make allowances for the loss of natural sunlight to the planet and probably a bunch of other stuff as well, but as a thought experiment it seems as doable as any of the other means and since it was posited in post 453 I thought I'd toss in my two cents.

    The problem of our social evolution being so far behind our technical evolution seems to be something almost overlooked in this thread. Even if we moved the entire planet in a fashion that would allow for life to continue as it is on this planet, the way things are going we'd likely kill ourselves off bickering over some bit of political nonsense long before leaving even the solar system.



    Mark @475: I suggest you read Accelerando before you condescend to me about exponential progress.

    Also note: Celera genomics did not get the human genome sequenced first: it was done via the academic community, the central work bankrolled by the Welcome Trust (a charitable foundation), on an open source basis. If you're going to be a free market cheerleader, at least try to get your facts right.


    This is why I enjoy hard science fiction. If you want magic wands and hand waving then stick to fantasy. I think Mr Stross's article presents some down to earth constraints that are almost always glossed over. I'm far more interested in a story that grapples with some of these issues then yet another simplistic Star Trek type universe. It doesn't mean they can't be overcome, it just means a writer needs to come up with something plausible that addresses these issues. If anything I think this would be a more interesting source of imagination then just drawing on the tired old sci-fi standbys.

    BTW Diaspora was a great book. Check it out guys.


    The last part of Charlie Stross's essay about not leaving earth until we have colonized the Gobi desert eliminated all our problems here is the same kind of thinking as

    "Let us not move out of our parent's house until the basement has been remodeled and every room is occupied with 1-3 people."

    Solving all of our family problems does not happen any faster whether we are all in the same house or whether we have spread out into more than one house. If you have guns and grenades or matches in the same house it is very easy to take out he whole family. The families survivability is better in multiple houses.

    This is unrelated to how well different family members get along or whether some people have a job where they can buy their own food.

    Also, the pure economic question could be why is Chuck saving money and trying to buy a place and move out and trying to buy a car when he could be pooling his money with the family to remodel the basement ? It must be that Chuck has fallen in with a bad crowd or has some kind of religion, otherwise why would he want to leave the house ?

    == Btw : so far the three day to 2 week camping trips in the backyard do not count as serious attempts to leave home.


    If the human population grows by 1% a year, then within a thousand years Earth will be insanely crowded. A multi-generational starship will not ship out enough persons to benefit those left behind, but even a cramped one may offer more living space than staying on Earth.

    Some rich, modern countries, such as Italy, currently have birth rates below replacement. That could buy a few centuries respite from population pressure, but each generation is born disproportionately to parents who like children. We will evolve towards a society that loves children. Childhood will be a magical time. Birth rates will come back up to replacement, rise above it, and the Earth will fill.

    The super-rich will move off-planet to get elbow room and privacy and to be allowed a third child. A half full multi-generational starship would permit 8 granchildren instead of 4 on earth. That might be all that is needed to start a journey from which there is no turning back. Or maybe the genocidal resource wars would rise from Earth to orbit so often that plutocrats and kleptocrats would find false hopes of multi-generational interstellar travel preferable to the true horrors of teeming Earth.

    One day, such a starship actually makes it all the way...


    In this context, the silent skies and the Fermi paradox have a simple answer: we may not be the first intelligent civilization to show up, but none of the others have succeeded in not only getting out of their own solar systems but doing so and prospering on a cosmological scale.

    This sort of ties back into your original post, though. It speaks to the fact that interstellar travel may never become practical for any civilization, due to the distances involved, the energy required and the other hard physical limits you specified.

    It's also possible that once you have the kind of technology it would take to make interstellar travel cheap and practical, there's no longer any good reason to do it. If you have access to virtually limitless energy and fantastic materials and information technology already, why travel elsewhere? I mean, if you had a fridge that filled itself up with whatever groceries you wanted, at will, why would you bother going to the grocery store? You wouldn't. Likewise, if you've developed advanced remote sensing and powerful virtual reality technologies, why spend the time actually visiting a world like Mars - let alone planets orbiting distant stars - when you could simply simulate them at home with 100% realism? You could explore the whole universe from your living room. There could be a trillion aliens scattered across the universe "exploring" earth at this very moment from the comfort of their own homes and we'd never know it.

    The bulk of technological advancement here on earth over the past 50 years or so hasn't come in the "macro" technologies invented during the past 100 years, like jet engines, nuclear reactors or rocketships - the kind of tech that would help enable interstellar exploration. The big advances have been in microtechnologies, like semiconductors, genetic engineering and nanotech materials that were invented during the same 100 year timeframe. To date, we've seen no reason why these trends would reverse - indeed, they appear to be accelerating, with microtech advances racing far ahead of what's been happening with macro tech.

    Our most advanced machines are growing ever smaller and ever more energy efficient. They're using less and less exotic elements to perform more and more work. Current semiconductors use silicon and some rare earths, but the next generation of computing devices may well be entirely carbon based. Can't get much more plentiful than that from a resource standpoint. No reason to go offworld to get more carbon. Especially not as information density continues to escalate as smaller and smaller subatomic particles are utilized to store information.

    The Fermi Paradox may well be explained by this kind of increasing reduction of scale when it comes to technology. Alien civilizations may continue to explore the universe, but they do so at subatomic levels because it's vastly less resource intensive and offers incredible rewards. Instead of exploring and exploiting the macro universe they harvest the vast richness of the subatomic world. Assuming they pass thru some sort of singularity and are able to project themselves down to the subatomic level they may vanish from the macro universe entirely, at least in any perceptible fashion from our viewpoint, but the amount of information and work they perform at such a scale could vastly outstrip anything we could hope to accomplish at the atomic level and higher.


    Sorry, Charlie!

    We will never colonize other planets? I believe you are correct. Not because of current technological limitations, but because humanity is poised to destroy itself. Such self destruction probably won't be complete, but will be a big enough setback that colonization of space will not be possible for a long long time due to socio-political reasons.

    Imagine the neo-humans on the West coast of Africa 100,000 years ago, looking at the vast ocean and thinking that, surely, crossing it would be impossible. "It would take a MAGIC WAND to cross this body of water," they must have thought. Of course, it was possible to WALK to the distant lands across the ocean sometime in the past, and it might be possible to somehow "walk" to a distant world sometime in the future. At present, that is but a pipe dream. Viking long boats did cross the ocean, then European sailing ships. Now ocean crossings are as routine as picking one's nose. Adventurous souls can do it in a modified BATH TUB if they so desire. Is a BATH TUB a MAGIC WAND? To us, no. To the neo-humans on the West coast of Africa 100,000 years ago? Most certainly.

    So our collective economy only runs on 4 terawatts of electricty right now? How much was it 200 years ago? Did you say ZERO? How much will it be 50 years from today? Try telling George Washington in Valley Forge about having a box that can heat food without warming the air around it. He would say you would need a MAGIC WAND for that. Human beings invented that. And the ability to power it reliably. Most of the energy from Sol goes into space, wasted. Why not build a ring world, not for living on, but for energy production? Start with the mass of Venus and build a solar energy belt around the Sun with microwave transmission stations beaming it various places around the solar system every so often.

    So, you say that there is no economic advantage to putting a colony on the moon, or on Mars, or on a planet orbiting a distant star? You are absolutely right. There was no economic advantage to putting a man on the moon. But there was huge economic advantage in developing the capability of doing it, which is the point that sailed high over your head. The economic advantage derived from building that capacity is far more than enough to justify the cost of doing it. Plus, doing it would be FUN (and scary, but mostly FUN). Human beings have crossed that ocean and climbed that mountain and landed on that moon, and they have had one hell of a time doing it. We will colonize the moon, and Mars, and build that ring. We will also colonize worlds orbiting distant stars.

    Charlie, you certainly have the right to whine and piss and moan about how doing all of this is "too hard" and about how these places are "too far away". I would certainly appreciate it if you would do it less proficiently and less loudly, however. You are hindering the efforts of the people who are, right at this moment, building the next BATH TUB.


    Karen@420: Obviously, this is just an engineering problem. If we can increase Earth's rate of rotation enough, space elevators become trivialy feasible. Close asteroid fly-bys could use tidal effects to do this gradually. ;-) More feasibly, we could always go for a hybrid approach. It should be trivial to have a craft to meet a free-hanging cable 100 km above and moving at Mach 3 or so relative to the surface of the Earth. The counter-weight cable would have to avoid GEO satellites, though.


    So, you say that there is no economic advantage to putting a colony on the moon, or on Mars, or on a planet orbiting a distant star? You are absolutely right. There was no economic advantage to putting a man on the moon. But there was huge economic advantage in developing the capability of doing it.

    Really? What was this "economic advantage" to putting a man on the moon, then? I mean, if you're going to assert something, you should be able to back it up with at least some evidence, the way Charlie did.


    Doug @444: The question of whether colonization is infeasible, or merely very expensive, is definitional of course. To me, "colonization" implies a large degree of self-sufficiency, and the ability to sustain activity in the absence of welfare assistance from outside (e.g., Earth).

    Note that self-sustaining doesn't mean isolated. Los Angeles or London are self-sustaining but wouldn't be so if isolated: Closed off all the roads, power lines, and water lines in or out, and bad things would happen quickly. The point is these cities have found a way to produce enough economic value to trade with rural areas (who have most of the food/power/water) and self-sustain as part of the larger ecosystem. As transportation costs have declined, the economic bar for cities to thrive has lowered -- one of the factors leading to increased urbanization.

    Will a human space colony need to self-sustain in the isolated sense, or will it be part of an economic network like cities on Earth? It depends on launch costs and what sources of economic value people find in space, and how these advance relative to our ability to build truly self-sustaining isolated systems. It's a race with many potential outcomes.

    True self sufficiency off the Earth is definitely not technically feasible right now. Remember Biosphere 2? We are currently unable to engineer complex self-contained ecosystems that actually work -- and this is just one of several challenges. The point is not that these things are insurmountable -- they probably are -- but that the way to really address them is via a path our society is not currently following. Big grand politically-motivated projects like the ISS do very little to get us closer to colonization.

    I suspect many of us here agree on the eventual goal. To me the issue is what should we fund right now to maximize our chance of getting there. Understanding the true nature of the challenge is a first step.

    487: 361 - I wonder what a Singularity of asshats is going to look like?

    A black hole, of course! :)

    342 – Will you settle for female SF readers? 343- If you have the technology to build colonies in space or on the moon or mars, then surviving on earth following a nuclear holocaust or dinosaur killer asteroid should be easy.

    Oh probably, but there are much worse things we could do to the planet than that. Nor was I talking about EVERYBODY leaving the place. Even so, take a look sometimes at what happens to island societies that ignore the ocean around them, or at most take fish out of it.


    In message 485, Dan Flanery wrote:

    Really? What was this "economic advantage" to putting a man on the moon, then? I mean, if you're going to assert something, you should be able to back it up with at least some evidence, the way Charlie did.


    Explosive advances in the industries of transportation, communications and computers have all been directly linked to the US space program in the 1960's. This has been extensively documented and shouldn't be too difficult to find if you would put a little effort into looking. I suppose that next, you are going to ask me to cite a reference "proving" that there were neo-humans on the West coast of Africa 100,000 years ago.

    Also, Charlie cited no references for his essay, as it was an opinion piece that was based on a particular line of reasoning. My response ran along the same lines.


    Don't beat around the bush. Future markets will rise for stuff in inospitable places. Stuff we don't know/want/need right now. I think my Dubai argument was quite clear on that. But you know it now as well as I did when I wrote it. We'll need that stuff. And that stuff will bring us closer to other stuff. It will make us more powerfull. Just as oil did.

    Dont you guys shift focus and turn on the weaker link on this side of the chain. I know, you know, there are some pretty crazy/moronic things beeing said defending the possibility of interstellar travel. Don't pick on them. Pick on the solid arguments, the ones made by sane people. I could go and defend my point of view by bashing somebody on that side of the fence too. You know I could. It's easy.

    I challenge all of you who agree with Charlie on this to deny any of the following statements:

    1 - Geniuses exist and revolutionize our scientific concepts. It has been so in our history many times. 2 - "Facts" of the past are proven wrong. It has been so in our history many times. 3 - New, very powerfull, markets rise for unlikely products. It has been so in our history many times. 4 - The technologically impossible becomes possible. It has been so in our history many times.

    Now, I've given you four statements. If I'm wrong, it should be easier to show that and make it clear. However, if I am right on all four counts, and if you read my previous two posts, it should be apparent that interstellar travel is indeed possible. In fact I would call it probable (personal view). Not certain though.

    Also, to the philosophers out there: please stick to proven facts (I've tried to). Don't throw lots of theories around. Give me proof, as I gave you. I have only talked about stuff that has actually happened.


    One thing is sure, don't get the flu. It can make a pessimist of anybody.


    I have cheap disposable items all over my flat that are magic. My phone, for example, would be magic to most people pre-Marconi. My ipod would be magic to anyone pre-Edison. Something as trivial as a reliable electricity supply would be magic to those primitives. We will have our magic wands, if we don't kill ourselves first.


    Explosive advances in the industries of transportation, communications and computers have all been directly linked to the US space program in the 1960's. This has been extensively documented and shouldn't be too difficult to find if you would put a little effort into looking.

    Where has it been "extensively" documented, and what specific advances have been "directly linked" to the US space program? I've seen this supposed fact blindly asserted over and over again, but whenever you research it you find out this technological advance that supposedly came to us via the space program was actually some pre-existing tech that maybe got a tiny R&D boost thanks to NASA - if that.

    A lot of it turns out to be stuff like Velcro and Tang, which already existed and was merely popularized via its links to the Gemini and/or Apollo programs.



    That was what I was talking about up in comment 264. Using a reasonably large mass launcher to launch stuff out the solar system at 0.9c (or faster, though that would leave out a biological payload).

    Upon rereading, I see that what was meant to be 0.9c, 0.99c etc suffered from some unfortunate typos that can only be explained away by the early hour. That is unfortunate, of course - I wish there was some editing facility :)

    I'm a little disappointed that noone bothered to comment on the idea. Cheap travel, at near lightspeed, is one of the things people point to as impossible, or something that might happen "thousands of years in the future". But we know how to do it, reasonably elegant, based on current science (if not current technology). Or maybe I just missed them among the myriad of comments involving 1000 year long travels, 1000 years of scientific progress, nukular hippie-run generation ships, the rectal-topological theory of the singularity, and suggestions about properly colonizing mums basement before venturing anywhere else?


    Also, Charlie cited no references for his essay

    Say what? Charlie's essay is riddled with hyperlinked references (there are over 20 in the first half!), and he shows his math.


    David @491 (and others): so, where's your personal jet car, your atomic powered automobile, and your packet of food pills?

    Seriously: you're suffering from observational bias. Sure you've got loads of fascinating gadgets scattered around -- but you're failing to notice the fascinating gadgets that for some reason have proven unreasonably difficult to mass produce. And there are a lot of them.

    This is not to say that there will be no breakthroughs of a seemingly-magical nature: just that we can't predict where they'll come from and whether they'll be any use to the project under discussion, viz. space colonization.


    Charlie@473: Wow. Wish I could average writing 1/50th this much per day. Behold, the power of discord.

    82k+ words, mostly poorly researched banter about space colonization. Why is this reminding me of reading NaNoWriMo novels? ;)


    Analogy check. Leaving Mum's basement involves getting a job. They won't pay you to do it otherwise. This should tell you something. You need a return on investment. Free markets, bitches!

    Dubai. Well, I've been there. It doesn't actually have much oil, but it's near places that do. Its core business is operating a really, really big container port. Again, where's the trade?


    martin t. @418:

    "Imagine an alien society observing earth at around 1600 AD, they have a view of earth as if they are looking on it with human eyes from our moon, it looks similar to their own planet so they launch their generation ship with 10000 people in hibernation. 400 years later they arrive and find a planet with aliens capable of destroying the planet several times, that are in continues conflicts with each other for resources and that are intelligent enough to realize that the visitors have the technology, resources and motivation to build such a ship and that they do not have the energy to turn around and fly home because earth is not available to them."

    Done. Harry Turtledove, "Worldwar". Seven book series. Half the Earth is conquered by aliens, and the ecology is even further screwed... but we win because we are more dynamic than they are and discover magic wands faster.

    Charlie @473: This essay ran to 4000 words; the ensuing thread, at 82,000 words (including the essay) would make a 250 page book.

    Yes, but it would need extensive editing, wouldn't it?


    I'm going to have to Go Away soon.

    Thing is, I do have a book to deliver in about six weeks' time, and only half-written so far ... which means I can't afford to waste several hours a day arguing religion with chuckleheaded optimists. (Most of whom don't pause to read the earlier comments before offering their own rehashes of same.)

    The book is, incidentally, a space opera -- one that needs to wave only one magic wand to make things work: and that a comparatively small one, compared to some of the more ludicrous wish-fulfillment suggestions on display here.


    Catfish@498: Nah -- Barbara Bauer would still rep it. And iUniverse would still "publish" it. Who needs standards when there are scammers out there waiting to help you out? ;)

    Or, you could Lulu it so that your parents and friends could buy a copy. Probably wouldn't be the first time someone turned a discussion thread into a Lulu book.


    David @491, but the point about magic wands is that they're unpredictable: they don't come along when you need them, and when they do they don't do what you expected them to do. This essay deals with what's predictable for a reason. It would be incoherent wish-fulfillment fantasy otherwise.


    Ciao, Charlie! Thanks for posting the essay and starting this (utterly mad, but still enjoyable) thread. Best of luck with your WIP!


    NelC @501, well, it would probably not be incoherent, because our host is a good writer. He does wish-fulfillment fantasy, and does it well. No reason he shouldn't examine the opposite side of the coin occasionally, and lots of reasons why he should.


    good luck with the novel, i like space opera, it is not hard scifi and does not make me think and gives me new insights to previously misunderstood or unknown concepts but it is damn entertaining.

    is there a place online to get to know a little bit more about this new novel?