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Thanks to James Nicoll for pointing out a fascinating paper explaining why factor 1,000,000 sunblock is inadequate when your star goes supernova, using a variety of concrete metaphors:

The energy flux would be roughly equivalent to having the entire earth's entire nuclear arsenal detonated a kilometre away, and would be sufficient to boil away the surface at hundreds of metres per second. Even on the temporarily protected night side, scattered light in the atmosphere and light reflected from interplanetary dust would far exceed normal sunlight, and radiation reflected from the moon would heat the earth to lethal temperatures if the moon were near full. ... We would expect the expanding atmosphere to propel a shock wave far into the night side of the planet and of course the air behind it would be at temperatures of thousands of degrees.
Luckily our particular star isn't going to go that way without some form of encouragement currently outwith the known laws of physics.


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This reminds me of the Harry Harrison (I think) story where stars are being used to burn all the garbage. As the influx of carbon-based garbage increases, the stars go supernova at an increasing rate. Harrison's hero resolves the issue by using a variation of the infinite hotel room problem.


And don't forget the neutrinos! A planet won't shield you from them, and the neutrino flux alone will be ebough to kill you. Opinions differ on the minimum safe viewing distance for a supernova, but nobody thinks it's less than a few parsecs.

But presumably you already knew all of this, considering the opening chapter of Iron Sunrise.


Infinite Hotel Room being the one where you can always fit in another 0.1%, another 0.01% and so on, ad infinitum?

I don't immediately see how that's a solution. Could you spoil the story for me, please?


The whole infinite hotel room thing (aka aleph-null hotel) relies on there being room for infinity.

And then the astonomers say "Olber's Paradox", and maybe even quote Edgar Allen Poe.

But the combination of "James Nicoll" and "supernova" is a worrying one for those of us who once prowled RASSF.


SPOILER ALERT (note: if spoilers are unacceptable, please let me know and I will refrain from further postings of spoilers)

The hero decides that, instead of sending the garbage into the stars, he will divide it into 20 pound packages and mail a package to everyone in the galactic civilization.

His reasoning is: 1. The civilization is expanding so there are always available recipients for the packages (infinite growth) 2. Some recipients will recycle some of the garbage (reduction in total garbage) 3. A large quantity of the garbage will be held in transit (dispersion) 4. Recipients who do not want the garbage will simply throw it out thereby causing it to be repackaged and resent.

Therefore, none of the garbage will have to be destroyed by sending it into a star.


That's ... hilarious! But doesn't it stink? :D Or was this Post-Singularity far-future garbage like bits of monopolium, left-over wellstone and the like?


Post-Singularity was supposed to be inside < strike> tags. I thought HTML worked in here ...


Only limited HTML tags work -- others are filtered out. You've got basic emphasis tags and one URL per post. I'll add strikethrough ...


Supernovae are so powerful that they coined a new unit to deal with the energy. It is the foe, defined as 10^51 ergs (thus, foe -- fifty one ergs).

A typical Type II supernova emits about 100 foe during the cataclysm, mostly as part of the neutrino flux from the core collapse. The sun, from intial fusion ignition to the final cooling to background temp, will emit about one foe over about 20 billions years -- depending on how fast the white dwarf cools down. The total energy release will be the same, it is just the time scale that is unknown.

You get enough iron in the core of a star, and bad things are going to happen.


While you're adding strikethrough, sup and sub (super and subscript) would be handy.


Erik: markup change done.

NB: Ergs not spoken here, I cut my teeth on SI units. (An erg is what? About 10-4 Joules, or something?)


1e-7 Joules, so a foe is 1e44 Joules.

Come on, don't you have /usr/bin/units handy? :)


In an alternate timeline where there was no French Revolution (and thus no metric system) how would we measure electric potential and current? The FPS system doesn't have any electrical units AFAIK...


Alternatively, a Type-II supernova is equivalent to 2 x 1030 megatons of TNT...


George Carty - SI electrical units are based on the others. 1 amp = that current which produces a certain force between two conductors a certain distance apart. It'd just be redefined in FPS terms.

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This page contains a single entry by Charlie Stross published on July 11, 2006 11:55 AM.

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