Satellites have the cost to launch which is pricey
Also satellites deliver a speed of light driven latency that doesn't work well for some important use cases
Facebook drone
Google balloons
]]>Alan finally closed the present in deep time thread, just about the moment I had another idea but wasn't near an internet connection. After thinking, it may be worth consideration and this is the least inappropriate active thread.
What about fast travel? Yes, we like it and it probably won't go away but one can make arguments why it should. (Hint: I was reading David Quammen's Spillover as Heteromeles suggested.) There are a few reasons to move people very quickly. On the other hand, a lower top speed for routine travel isn't unthinkable in most cases.
Ocean liners took several days to cross oceans and this was generally fast enough. The recreational resources of liners were so popular that they've been re-created as cruise ships today. The packet sized can be very large and with modern communications passengers don't need to be out of touch.
Overland long distance trains are a known and established technology. Not as big as ocean liners, they still have people who rid them just for fun. Maximum speeds of 100 to 200 kph seem perfectly practical for typical continental routes. (Naturally there are exceptions such as the DHR.) How many people really need to cross Eurasia in a matter of hours?
If there are many diseases, new or old, then a de facto quarantine period may be popular, even mandatory. And many commentators on the thread seemed to like low-energy models for the 31st century. I'm not sure that's very plausible, nor that the energy use per passenger mile is much less for ships than airplanes, but it's at least as plausible as many other things SF has offered us. Perhaps we'll be remembered for a brief and anomalous period of freakishly fast travel. We even built a supersonic passenger plane!
]]>In any case, the British Empire did just fine running with nothing faster than ships, as did the Spanish and Dutch empires before it.
There's probably some way to link this into Kessler Syndrome and colonization of the Moon, Mars, etc. and travel times vs. political control.
]]>Fast travel times for people are only necessary if you don't have high quality intercontinental communications. When anyone can phone a friend in London from New York there's much less need to build expensive machinery to shoot humans through the air at hundreds of knots. So logically a Kessler Cascade that took out satellites would encourage more long distance travel - since people couldn't easily and quickly send small messages we'd have to fall back to actually shipping humans around more. The reciprocal model may also work, substituting phone calls, email, and telepresence for actually hauling human bodies around at uncomfortable speeds.
Hypothetical future empires will certainly want to move diplomats and military power to trouble spots very quickly, but it's not necessarily clear that hours are that much more useful than days. The British Empire did well for a long time with everyone knowing that while the Royal Navy might be months away, troublemakers would in time wake up to find seriously Oh Fuck numbers of warships off their coast.
]]>Plus the Skylon just looks so cool, like a 1950s sci fi spaceship on a pulp cover, or a V2 on it's side. That it's not getting huge government interest tells me exactly where governments hearts are. The freezer, that's where.
]]>Drones may be flavour of the month right now but neither Google or Facebook have a great record in profitable innovation outside of their Global Ad agency niches.
]]>In the event of a Kessler incident it's hard to imagine one of those two approaches not picking up the slack
]]>I don't think there's currently any known material that can absorb high speed particles without disintegrating itself. Maybe a wad of Kevlar.
]]>It's counterintuitive, but if a speeding speck of debris is likely to become a ball of plasma when it hits anything, then putting just a wisp of matter in its path can be better than putting a heavy sheet of matter. You get the same ball of plasma either way, but you don't get the structural disruption in something that doesn't have much structure to disrupt, like an aerogel or a Whipple shield) (vs. say battleship armor), nor do you get debris spalling off from the explosion.
The problem is that, even though you can shield a smallish volume fairly effectively against small debris (they do this already on the ISS), you've still got large, fragile solar panels, radiators, antennas, sensors, and windows. And you still have larger debris that need better solutions than this.
Perhaps we need to have the orbital equivalent of spittle bug satellites, that sit up there inflating balloons and filling them with aerogel, and then giving them a mechanism to deorbit each balloon when it's collided with enough junk to be less than useful.
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