The Impossibility of Colonizing the Galaxy

OriginalArlen writes "The science fiction writer Charlie Stross has written an excellent and comprehensive explanation of why, thousands of SF books, movies, and games notwithstanding, human colonization of other star systems is impossible. Although interstellar colonization seems common-sensical to many, Charlie makes a clear-headed and unarguable case, so far as I can see, that it ain't gonna happen without a 'magic wand' or two. Nevertheless it would be interesting to see reasoned responses from the community who believe that colonization is not merely possible, but inevitable — and even, as Hawking has said, vital for the survival of the species. So, who's right — Hawking or Stross?"

Assertions

[Enselic]

"So, who's right -- Hawking or Stross?"

They are not saying opposite things, one is saying that we can't colonize other solar systems, the other that we must. They are probably both true.

Executive summary

[charlie]

I'd like to note that I'm not saying space colonization is impossible per se ... but that (a) it is really really difficult without breakthroughs in a number of key technologies (that we can't be certain will happen), (b) we're not going to see any economic return on investment from it, and (c) the motivations for it are essentially quasi-religious and ideological in nature.

Using "the high frontier" and appeals to settler gumption and heroic individualism isn't the right paradigm; if it's going to happen we need to abandon certain cherished illusions (dwelt on at length) and start doing some hard thinking about what we really want.

Re:Can we get the tech to continuously accelerate?

[Catbeller]

Not just them. It's just a physical fact. Acclerate for 1 G for a year and you reach speed c. How one does that is another matter; how to shield yourself from hitting a "penny" at that speed and turning into plasma is another. Light, infrared and radio waves hit head-on would violet-shift into x-rays and cosmic rays, so you have to shield for that as well. And then there's the matter of navigating when you can't see out.

Re:Clarke's first law

[Have Blue]

Bussard ramjet

I think the current view is that the efficiency of these things is questionable at best.

Suspended animation

It will requires several miracles in molecular biology before we can hibernate the way other mammals can. And no known organism larger than a microbe can survive for the durations interstellar travel will require.

Generation ships

Requires the ability to do space construction on a large scale, which requires a thriving space industrial presence, which requires several miracles down here first.

Impossible?

[SlayerDave]

I read the entire article (which was excellent and well-reasoned), and nowhere did the author say space colonization was impossible. His argument is that it would be prohibitively expensive and technically impractical, but certainly not impossible. Colonization, especially of extrasolar planets, is extremely unlikely, but it is definitely physically possible, given the economic and and political will to do so.

Very bad summary, subbie.

Re:Clarke's first law

[hankwang]

it will only require one.. a method for freezing water that doesn't cause it to expand.

It already exists. Cooling water to 250 K (-23 C) at 3000 bars will do the job. Unfortunately, the pressure rather than the ice crystals will kill a human being at that type of pressure.

Impossible isn't what he said

[HiThere]

He said "without a magic wand". Then he listed a couple of possible magic wands.

FWIW, he neglected (not missed, merely skimmed over) "MacroLife", which would allow glactic colonization without magic beyond nuclear fusion...but *wouldn't* be particularly economic. Perhaps.

Since the MacroLife concept isn't widely spoken of, let me elucidate:
1) You build a space-based factory.
2) You build a colony nearby to manage it.
3) People get comfortable living in the colony, and enlarge it, and make it self-sufficient.
4) There's a political dispute.
5) People living in the colony attach an engine, and depart slowly for "elsewhere".
6) You don't want a tremendously high speed, because you collect materials along the way.

This will require large numbers of technical advances. Closed cycle life support systems are only one of many, but the only one that approaches "magic wand" status is controlled fusion. (I don't think that fission would suffice. Refueling would be too difficult.)

Note:
1) This is slow.
2) This isn't something that one intentionally creates.
3) Most of the colonies will probably decide to stay put. That's fine, while in situ they provide a net economic gain.
4) Espect to have, perhaps, 5 colonies departing / century on an average, with a fairly large population of colonies.
5) The motives will be political or religious rather than economic. Those who leave must be prepared to suffer a considerable economic hardship.
6) The colonies need to contain a viable population. This probably means 5,000 people and a staic population...though various work-arounds are possible.

Conterindicators: Advanced robotics would probably mean that the space colony wouldn't be overseeing the running of the space factory, but it might be a way for an initially wealthy group to excape overpopulation, and the associated governmental restraints. Or there might be other motives. Or there might not. This whole thing could be a "could have happened, but didn't".

mundane SF proponent?

[mrmeval]

He sounds like one of the mundane SF proponents. Mundane SF is the idea that there never will be nanotech, there never will be AI, there never will be space travel....you get the picture.

Re:Both right?

[LionKimbro]

Have you ever read Stross?

He's not exactly what we would call a stranger to the concept of the Singularity... [accelerando.org]

If I've skimmed TFA correctly, what he's saying is that it's Post-Humans that are going to go afield; Not what we today call "humans."

Re:Both right?

[CaptKilljoy]

>Yeah, but wasn't it pretty well accepted belief back then that you could never break the sound barrier?

No, that was a myth created by ignorant journalists. From http://history.nasa.gov/SP-4219/Chapter3.html [nasa.gov]:

The first situation was that of a common, public belief in the "sound barrier." The myth of the sound barrier had its beginning in 1935, when the British aerodynamicist W. F. Hilton was explaining to a newsman about some of the high-speed experiments he was conducting at the National Physical Laboratory. Pointing to a plot of airfoil drag, Hilton said: "See how the resistance of a wing shoots up like a barrier against higher speed as we approach the speed of sound." The next morning, the leading British newspapers were misrepresenting Hilton's comment by referring to "the sound barrier."41 The idea of a physical barrier to flight --that airplanes could never fly faster than the speed of sound-- became widespread among the public. Furthermore, even though most engineers knew differently, they still had uncertainty in just how much the drag would increase in the transonic regime, and given the low thrust levels of airplane powerplants at that time, the speed of sound certainly loomed as a tremendous mountain to climb.

The same source also notes:

But Mach devised a special optical arrangement (called a shadowgraph) by which he could see and photograph shock waves. In 1887, he presented a paper to the Academy of Sciences in Vienna where he showed a photograph of a bullet moving at supersonic speeds.

Re:Leave science to the scientists

[ceoyoyo]

It's much less likely that an alien microbe will affect us in any way than it is that we'll be able to step out of our space ship and eat the local fruit. In other words, very, VERY unlikely.

Even here on Earth, most infectious microbes infect one or maybe a handful of species. The really promiscuous ones infect a bunch of closely related species. Now consider that from a cellular biology point of view (that is, the microbe's) most of the organisms on the planet are nearly identical.

You expect to step out on an alien planet and have the local microbes go "ooh, human! We've been waiting for this!"??

Re:Both right?

[The One and Only]

Moreover, Einstein claimed the speed of light is a constant, and as IBM's experiments earlier this year have proven, the speed of light is actually a variable.

sigh No, they did not prove that c is a variable. c is still a constant as far as we can tell--the fact that light doesn't always travel at c in specific circumstances is useful information that in no way disproves Einstein's theories. Like a Star Trek writer, you're substituting enthusiasm for knowledge. Enthusiasm does not change reality.

By scientific consensus, we believed the Earth was flat, until we were told it wasn't. We attacked the naysayers and tried to have them killed...

The ones behing killing people were upholding a religious consensus--even the ancient Greeks knew the world was round.

As long as there are people saying that we can't do something, there will always be people telling them to shut the hell up, who will defy the odds and fly like an eagle or reach out into the stars. Don't let typical human apathy take hold of that which is grand.

And the people who do these things are the hard-headed types who accept reality and deal with it honestly. Sheer enthusiasm makes you that guy jumping off your roof with a 5-winged human-powered flying machine.

Re:Both right?

[koxkoxkox]

I think the whip is the most primitive device breaking the sound barrier. It dates back quite a bit ...

Re:Can we get the tech to continuously accelerate?

[dkf]

Acclerate for 1 G for a year and you reach speed c.

No you don't. Relativity 101. It takes an infinite amount of energy to accelerate a mass (any mass) to the speed of light (because of Lorentz contraction). Indeed, applying a 1g acceleration for a year would only take you up to 215332822 m/s (i.e. a bit under 72%).

(To work this out, compute how much momentum would be transferred to a 1kg object undergoing a 1g acceleration for a year, which I make to be about 309264480 kgm/s, and then solve the Lorentz equations [wikipedia.org] to compute the velocity relative to the initial "rest" frame from the momentum. Trivial really.)

Re:Leave science to the scientists

[jstomel]

The likelihood of any hypothetical "bug" from an alien world being being biochemically compatible with humans is very very tiny. It approaches zero. Even if we and it are descended from the same pangenic life spores, we would have evolutionarily diverged a long, long time ago. The odds that we would be able to go out on a hypothetical life inhabited alien planet and just be able to eat whatever happens to be growing is larger, but still very small. However, assuming said life is carbon based, the odds that there is some feasible chemical process we can use to convert said native life into something that can be digested by humans is actually not that bad. After all, given enough time and energy you can convert almost any form of organic matter into ethanol, which can be turned into glucose through a reverse fermentation process.

Re:Can we get the tech to continuously accelerate?

[jstomel]

Errr....Wellll.....actually it doesn't matter if you accelerate the vessel or the whole universe except the vessel. The principle of no privileged reference frame means that these are identical statements.

Re:1800's logic though that travelling100MPH=death

[MadnessASAP]

Actually AFAIK the deep space between solar systems should be pretty clear of anything really that big, In fact once you're past the asteroid belt where all the gas giants basically sweep up any loose bits of rock you should be pretty much in the clear. After all the Voyager and Pioneer spacecraft have been going for years and they still haven't hit anything and a few of them have passed pretty close to planets and other sources of rocks.

Re:Both right?

[arminw]

.....c is still a constant as far as we can tell....

Actually since the speed of light has been measured for the first time t has declined by about 4%. The speed of light is determined by the medium it traverses. Space is not empty, but has certain electromagnetic properties. As space has expanded from the time of the big bang, its properties have changed dramatically. By a factor of at least 300 million or more. Light used to travel MUCH faster through the denser space of long ago.

Therefore any equation that has a "constant" in it that relates to "c" will be different accordingly.

Re:1800's logic though that travelling100MPH=death

[Anonymous Coward]

Well, actually, the guy you replied to was wrong... Quantum entanglement can't be used to transmit messages over a distance. Basically, in the example he gave, those spins have to start out random and unknown, NOT a message. So all you're doing is ensuring that two labs simultaneously (and here I mean the faster-than-light kind of simultaneously not the special relativity kind) get the same random numbers.

It's cool and trippy but useful as a Star Trek communicator it is not. It has applications for encryption though.

-Physics student.

Re:Both right?

[VolciMaster]

Last I checked, light travels a lot slower in denser materials (ie: speed of light in air versus in water)