Wednesday, June 19, 2013

The Arithmetic of Interstellar Travel Revisited

I gave the subject short shrift, but considering I was a little busy at the time, I forgive myself.

As Quiggin pointed out, sending 10,000 colonists to a planet 1200 light years away requires a multi-generational ship that can survive in interstellar space. Any civilization with that ability has no need of planets. I'll go further and say that any ship that can survive in interstellar space must not only be self-sustaining and self-repairing, it must by definition be not only a world unto itself, but a world that can self-replicate. In which case, all such a ship needs is a decent energy flux and some mass to exist and reproduce. Planets? Nebulae will work as well. Dust clouds. Ah, but with one slight proviso, that I'll get to in a minute.

Well, fact is sending canned ape to the stars is probably the worst idea ever conceived. If it happens, and I doubt it will, it's going to be robots that do it. Or some unknown magical technology that various speculative fiction authors have played with.

But let's get to the more interesting possibility of 10,000 colonists on the Moon by 1978. As I once pointed out, there were plans to continue lunar exploration. But the fact is, no plausible scenario can be created that would have resulted in a lunar base. Public interest simply wasn't there. Even the one demographic which was supersaturated into a maximal sugar high - the youth of the 1960s - couldn't sustain any realistic interest. And the Mundanes - the lumpen-proles drinking beer and watching black and white television shows - displayed the appropriate interest at the appropriate time (the Apollo 11 moon landing), and then moved on. Perhaps, if, say, we were a sane species, and had not invested some tens of trillions of dollars in mutual assured destruction, perhaps there might have been room for a moonbase in the 1970s, but that was not to be. So, the social incentive was not there, could never have been there, unless it had turned out that something remarkable was out there that was worth investigating/exploiting/avoiding.  You know, TMA-1, extraterrestrial amazon babes, or moon dust gives men giant stiffies, or some such thing.

Interesting thing, though, about that MAD program. As Neal Stephenson points out (as pointed out to him by Dr. Jordin Kare), you don't get the Moon Stunt without the insanity, or at least a semi-improbable series of events that results in rockets big enough to hurl large payloads into orbit contingent upon:
1) Mid-20th century world's most technologically advanced nation under absolute control  of superweapon-obsessed madman develops rockets
2)  Astonishing advent of atomic bombs at exactly the same time
3)  A second great power dominated by secretive, superweapon-obsessed dictator
4) Nuclear/strategic calculus militating in favor of ICBMs as delivery system
5) Geographic situation of adversaries necessitating that ICBMs have near-orbital capability
6) Manned space exploration as propaganda competition, unmoored from realistic cost/benefit discipline
That's Stephenson presentation. Allow me a different wording. Nazi Germany creates basic rocket technology which cannot hit shit. America creates fission bombs using 1930s theory and 1920s technology. Stalin threatens to lop off heads if he doesn't get both technologies for his birthday. Rockets and H-bombs are a marriage made in heaven as rocket's guidance systems can barely hit the broad side of a city, H -bombs are only good for destroying cities. Mutual targets in the USA and USSR require rockets that can reach orbit. Other things the size of H-bombs, like communications satellites and space capsules can be launched. As a result, the Apollo program is the greatest triumph of Communism ever.

(And, of course, let's not forget the burgeoning computational and data processing industries, created by the Federal government due to the fact that targeting cities with H-bomb using 1930s-style electronic brains with vacuum tubes and switchboards was horrendously inaccurate and wasteful, much more sophisticated electronic computers were required to the job, thus subsidizing all of those libertarian code-monkeys literally into existence, but that's for another time).

It would seem that had the original Apollo program been carried through, with ten moon landings, followed by a semi-permanent lunar base, followed by a more permanent lunar laboratory, there was a chance that many of the things we know now (water on the moon), would have made a colonizing effort more palatable. Ignoring the total lack of public support, could it have been done? Could a colony of 10,000 have been established by 1978.

The answer is yes. But a qualified yes. I'll not go into the space geek stuff. Clearly, turning Detroit into Rocket City, getting launch costs down through an economy of scale from cranking out space ships like sausages, is believe it or not, the easy part. (And think of what Detroit would look like today? Wow!) Again the greatest difficulty about building nuclear rockets is not the technical aspect but the legal and diplomatic ramifications of having the danged things fly over your airspace. That kind of technical wanking, though fascinating is actually the minor part.

The biggest problem is all the deaths. If prior colonization efforts are to be used as comparison (most fairly successful under more or less optimal conditions of having air to breath and water to drink), then perhaps the closest analogy to a permanent moon colony would be the distastrous colonizing history of Jamestown. Famine, inclement weather, hostile natives, resulted in about a 80% mortality rate for English colonists. I would expect the same for Moon colonists. So, to get 10,000 hearty souls to thrive on the Moon by 1978, I would expect at least 50,000 Americans must die. Well, what's that? Less than World War I, more than Vietnam. Could Americans accept that death toll without hostilities to justify it? I kind of doubt it.

And then, that proviso I mentioned? There's the really big bugaboo, the elephant in the room that no one really wants to address. You know the basic rule of real estate? Well, in space exploration, it's radiation, radiation, radiation.

The average stay on the ISS is about 200 times as bad as smoking a pack of cigarettes a day for a year. I don't know if that's true, but it can't be far off. And living on the Moon is not that much different. Oh sure, you can live underground, but it's amazing how living 100 miles at the bottom of an ocean of air can protect you from all those really nasty things that a Moon bunker can't protect you from. Cosmic rays - near-light-speed atomic particles, gamma rays, shit like that, just tears right through you. It would seem, if you want to exist in space, you would like to come up with some type of material substrate for consciousness that eats gamma rays for breakfast, that actually thrives on being composed of unstable nuclei. Robots won't hack it. Conventional electronics get fried. What's a boy to do?  I don't know, but no conventional matter will last long on the lunar surface. You got to dig down, like way down, like kilometers down below the surface. Have fun with that.

Which, of course, addles your already insane cost/benefit calculations. Bummer.


6 comments:

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    1. Yes, I 'm aware of that. http://engineering.dartmouth.edu/~d76205x/research/shielding/
      It should work for solar wind, protons, alpha particles and cosmic rays (relativistic nuclei below, say, 500Mev-1Gev in energy), but for things like neutrino flux from supernovae, gamma rays from gamma ray bursters, and ultra-high energy CGRs, magnetic shielding just ain't gonna cut it. Promising alternatives, but still in the pipeline, would plasmonic shielding, or metamaterial cloaks involving wakefield configurations. My guess, if you get that, then you got fusion power, which makes space travel even less likely, as you can do more here on Earth with ultra cheap energy than out in space (cost/benefit wise). The Universe oozes Irony.

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    2. Why is it again that with compact fission reactors we're not ion-driving all over the solar system?

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    3. Fucking lawyers. And CYA politicians. Should have left it to Rickover. He never made a lemon.

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    4. My boss is a retired commander and one of Rickover's boys. Nuclear and electrical engineer, best boss I've had in 28 years. I can see a fleet of nuclear spacecraft in sync with Kubrick's visual design sensibilities ferrying men and material to and fro. Matter fact, a gritty alternative history serial narrating that would be pretty cool. Rickover's nuclear interplanetary Navy...,

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  2. "March 9, 1959. Rep. James G. Fulton, Dormont, Pa. (R) proposed that Rear Admiral Hyman G. Rickover, so-called father of the nuclear submarine, be asked to help develop a nuclear-powered space rocket". There's your divergence point. By sheer coincidence, Westinghouse Astronuclear Laboratory and Bettis Atomic Power Laboratory were in Fulton's congressional district. He also set up a last minute compromise to save that magnificent white elephant, the Space Shuttle.

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