Friday, March 25, 2011

Never trust an astronomer with a sinister goatee

Okay! So! This post has been sitting around in my Drafts folder for like four months or something. It is all outdated planetary news by now. What I really want to talk about is TYCHE!!! 'cause OMG TYCHE!!!

But Gliese 581g still matters too, so here it is, the report on the previous go-round of the planetary enthusiasm/disillustionment/enthusiasm carousel:

You know, nowadays I consider myself mostly kind of an eye-rolling jaded sophisticate as far as interstellar settlement goes. While I'm moderately bullish on humans making some interesting use of the rest of our own solar system someday -- God willing -- I scoff at FTL drives and galactic empires, and even managing a quick trip (by biological humans) to Proxima Centauri seems honestly like it's going to be a matter of several millennia from now at best.

I'm not really talking about engineering, here; we know perfectly well how to build something that could push a small craft a few light-years, and do it in under a century. I'm talking economics, and sociology, and technological history, and ecology. (If you want to know my exact reasons for thinking this, you can read the massive essay below, after the cut. I moved it there because that wasn't really going to be the point of this post.) I think that, in all likelihood, we are stuck living in and around Earth for a long while. And we are stuck in this solar system for a long, long while after that.

So we're not going anywhere; and Wittgenstein's Lion says that even if there is someone very complexly made out there, they are unlikely to be broadcasting prime numbers, never mind schemata for cold fusion reactors, on radio frequencies in our direction. Very likely there is somebody out there, for sufficiently broad values of "somebody" -- and very likely those values are so broad that we will have, essentially, nothing to say to each other.

So the issue of life on other worlds is, in the end, a matter of pure academic curiosity. Right?

But [a few months ago, when I originally wrote this blog post], when I read in a news headline that they'd found an earthlike planet, I burst out crying.

Given my jaded sophistication and all, this was quite a surprise.

It turns out I've been waiting my whole life to read those words: earthlike planet found.

And despite all my sophistication, despite my general environmentalist attitude of "let's tidy up here a bit first, shall we?", my first overwhelming thought was: we have to go. Now. We have to go now. I found myself desperately calculating: 20 years, maybe, to build a tiny probe with a massive solar sail and a big laser at L5 to push it? -- or else one of those doohickeys driven by exploding nuclear bombs against a plate? Could we get it up quickly to, what, half the speed of light, and have it do a flyby? That's another 40 years, maybe, and 20 years for the signal to return -- eighty years from now I'll be 121 -- that's doable, right? I could hang on until word came. That we are not alone. That this fragile globe is not our only shot.

(Now, some months later, they are finding so many bushels of extrasolar planets in the right zone, that it is already a little hard to remember how shocking that headline was; which is one reason to blog it now, and mark that historical moment...)

The putative planet, Gliese 581g, is a Goldilocks planet -- the right distance and size from its star for liquid water. We already know there's some water on the Moon, Mars and -- our best bet for finding life larger than a microbe in this solar system -- Europa. Also, with a little patience, Kepler is likely to find earthlike planets actually traversing the surfaces of their stars from our perspective, allowing us to actually look at their atmospheres' spectroscopy for signatures of life. So it's not like Gliese 581g is our only chance. But still.

So it was with consternation that I read a href="https://www.dailymail.co.uk/sciencetech/article-1320539/Gliese-581g-exist.html">the news that a team in Geneva was unable to find the planet, analyzing (most of) the same data. When I read the article aloud to Noah Sunday morning, I could not help reading the comments of the Swiss team's leader (who does have a sinister goatee) in a leering and menacing Swiss-French supervillain's accent, peppered with scare quotes, italics and ellipses. (Try reading it yourself that way, it's very convincing.)

Come on, Gliese 581g. Hang in there. Exist!

Interstellar-exploraton skepticism after the cut:

The science fiction I grew up reading tended to see interstellar exploration by analogy to humans exploring distant parts of Earth -- mostly through imperialistic colonization (either imagining ourselves as colonizers -- benevolent or malevolent -- or as the colonized); sometimes via the settling of actually empty lands; sometimes as cross-cultural encounter, trade, syncretism.
It seems now (I'm with the Mundanes on this) like this was only possible by virtue of a kind of willful self-deception, by kidding ourselves about the actual scales and costs involved, and the alienness of what we would find.

Human voyages of exploration -- other than the one to our Moon, and to some extent the poles and Himalayan peaks -- have always been predicated on the notion that you'd would at some point get somewhere that was exploitable, where things were rather like they were at home. There would be something to eat, at least, and probably someone to talk to (who, however culturally different, would have the identical hardwired neurology -- would see, hear, taste, smell, laugh, cry, look surprised, look angry, look confused, point to things -- all of which you'd need to bootstrap a common language). If you were lucky, these someones would have aggregated a bunch of recognizable stored value, which you could trade for or pillage to pay back the investors back home (worst case, you could kidnap the someones themselves as trophies or labor).

You could also pretty much count on there being air.

Applied to human space travel, that analogy -- the "somewhere exploitable to get to" analogy -- is, for the foreseeable future, totally false and misleading. What do I mean by "for the foreseeable future?" Well, first, until we are at a point where we can say "molecules already assembled into complex carbohydrates and amino acids and vitamins and so on? Nah, that's okay -- just give me the raw elements and some light energy and I'll put it together, and flawlessly, and not just at research-prototype or even industrial-application levels but at rock-solid-bet-your-life-on-it levels of reliability, and not for just most of the things I need but for all of them, even if something goes really wrong." At that point the Kuiper belt is as hospitable a home as Earth, and at that point we are also probably not anything like recognizably human anymore.

This false and misleading analogy has totally distorted our thinking about space.
Rather than the Neolithic or Viking or Spanish arrivals on America, or the South Sea islands or Australia, the correct historical templates for the foreseeable-future exploration of space are the moon landings, and to some extent the summit of Everest, or Antarctica farther south than birds venture. We go somewhere, bringing everything with us that we need, in a little package -- look around quick before the nonrenewable aspects of the package run out -- and get the hell home. The longer we go for, the more things we need, and the more aspects turn out to be nonrenewable; and I suspect the curve of complexity vs. time is worse than exponential.

Now, this doesn't mean we won't get to the point where we have some folks living on Mars or the asteroid belt, even beyond tourists, explorers, and scientists. There may be some actually economically viable niche there, mining or constructing something in the rest of the solar system, sometime this century.
But I think it's pretty goofy to imagine substantial amounts of the human population (as opposed to isolated industrial groups, like polar stations or oil rigs today), while we still look anything like us, living off Earth. Again: this is not so much because it's technically impossible, engineering-wise, as because it's not historically and economically valid.

We don't just do things because they are technically possible. Here's an example:

It would have been technically possible for a substantial proportion of Europeans at the time of Periclean Athens to have left the land, and lived permanently in floating raft settlements in the Mediterranean, never touching the coast, living from fish, cultivating floating gardens, using dried seaweed for fuel, figuring out how to survive storms and fend off pirates, trading dried fish and pearls for bronze vessels to boil and desalinate water (Archimedes could totally have solved the desalination problem, I bet). I feel like that's about as technically feasible as twenty-first or twenty-second century humans building massive orbital habitations and Lunar and Martian cities.

But it didn't happen because it would have made no Zeus-damned sense. Iron Age Europe had plenty of sailors, and some individuals who even lived for years at sea without touching down on land. But a city on the sea?

Imagine Athenian philosophers or politicians advancing this argument: "but we need to get a bunch of humans away from the land and onto the sea, so that if some horrible calamity like plague, war or mega-earthquake destroys everything on land, humans will survive somewhere!"

Surely the two sensible responses would have been:

1. "What? a settlement at sea is never going to be totally independent of land -- how will the sea dwellers mine metals, for instance? And if they have constant commerce with land, how will they be immune to plague or war? And as for natural disaster, won't they be dramatically more vulnerable in that regard?", and
2. "Who exactly is going to pay for this?"

   But even after we reach the point that we have major orbital habitations -- long after we fill up more useful, hospitable, and available niches like the ocean floor and the polar regions -- the nearest stars will be far, far out of reach.

   At one point David Moles and I were doing some back-of-the-envelope "economic" calculations (I don't have them any more, do you, David?). The idea went something like this: if we treat energy as roughly analogous to money, and assume that the "GDP" of a very sophisticated future human civilization is equivalent to capturing the entire energy output of the sun (e.g. by building a Dyson sphere around it), what percentage of that "budget" would a "business" -- as opposed to "exploratory" -- voyage to Alpha Centauri take… by which we meant, sending something the size of a van, decelerating it to orbit around Alpha Centauri, and then bringing it back, all within a current human lifespan, shipboard time?

   The answer was a lot. A lot of that Dyson-sphere energy budget. As I say, I don't remember the numbers (maybe someone will run them for me), but it was not equivalent, in terms of the 2010 US GDP, to sending a truck from Boston to Mobile. It was more like, say, the Afghanistan war. It was not something you were going to be doing a whole lot of.

   It doesn't mean you don't -- at some point -- send someone to go look around. But it means you are pretty much never -- for pretty extensive values of never, like "until discovering magic energy undreamt of by current physics" values -- going to be regularly shipping trade goods back and forth, or supporting a colony that needs any kind of material or low-latency informational support.

   Which means that, I think, the most likely scenario for ultimate "human" settlement of other solar systems is not Columbus, or Vikings, or Rome, or the American West, or any of that stuff. The right historical analogy looks more like this:

   Twenty-first century humans, in this analogy, are Australopithecus afarensis, barely avoiding leopards in Olduvai Gorge and working out the idea of sharp rocks.

   Alpha Centauri, in this analogy, is Tasmania or Terra del Fuego.

   Sometime long, long in our future there's some other kinds of us -- many kinds, many transformations and false starts -- that will slowly, slowly percolate through this unimaginably large space, region by region, figuring out how to adapt themselves to each intervening ecosystem, inventing new technologies and new ways to live and developing new cultures.

   The "us" that settles around Proxima Centauri will be distant descendants of an "us" that was quite comfortable in the Oort cloud, and couldn't remember any more why anyone would want to live near (or in) a gas giant… never mind on the surface of somewhere rocky, small, warm, and wet.

   Posted by benrosen at March 25, 2011 02:45 AM | Up to blog
   
   Comments

   Oh, and uh, when I say "eye-rolling jaded sophisticate" I mean, within the set of overexcited SF geek fanboys who think scoffing at FTL drives is a shocking sign of world-weariness!

   Just in case that was unclear.

   Posted by: Benjamin Rosenbaum at March 25, 2011 11:32 AM

   1."What? a settlement at sea is never going to be totally independent of land -- how will the sea dwellers mine metals, for instance? And if they have constant commerce with land, how will they be immune to plague or war? And as for natural disaster, won't they be dramatically more vulnerable in that regard?", and
   2."Who exactly is going to pay for this?"

   I expect the second one has had far more stopping power than the first since we started swapping pointy sticks for pretty rocks. I can see it as a sign of our true human origins well after we leave the Oort cloud.

   But I agree, just because it can be done, technically, doesn't mean it should (but I still kind of want a solar-powered flying car and a condo on the Moon - I blame Robert A. Heinlein).

   Posted by: Sarah W at March 25, 2011 03:16 PM

   *pat pat* It's okay. I promise, they'll find another one before long, and it'll be real. And then they'll start finding bushels of them, too, and some of them will be even closer than your putative buddy Gliese581g. And then you can apply for work at some crazy materials company puzzling out how make that nice space elevator.

   Posted by: Jackie M. at March 25, 2011 07:48 PM

   In the mean time, if all the gas giants have got you down (no really, all those gas giants GUARANTEES there will be terrestrials discovered soon, we just need more money and slightly cleverer instrument) this wikipedia article makes them kind of fun:

   https://en.wikipedia.org/wiki/Sudarsky_extrasolar_planet_classification

   (I didn't know there was a system for classifying them! It's even name for a guy I knew in Tucson. Huh!)

   Posted by: Jackie M. at March 25, 2011 07:55 PM

   There is no reason to think that water is necessary for "life forms" any more than carbon is. Also. a life form might be made of non-contiguous elements, something like an ant hill or a bee hive.

   In general, it is close to impossible to define what "life form" means, much less "intelligent life form".

   Posted by: DMR at March 26, 2011 04:42 AM

   Well sure -- I'm all about the non-carbon-based life forms, and the difficulty of defining life and intelligence. Still, I find myself passionately interested in the question of whether there is something that would impress me as being enough like life out there. This is of course a recursive definition, akin to Damon Knight's of science fiction. Water, free oxygen, etc., is none of it either necessary nor sufficient for "life" -- but the question is what can we detect at a great distance, which would look like a good bet.

   Posted by: Benjamin Rosenbaum at March 26, 2011 04:44 PM