So today I went to a talk by Lee Billings, author of Five Billion Years of Solitude (which, note, I haven’t read yet, although I now have a signed copy; I’ve just heard the talk).
He is all about how incredibly cool it would be to find out that there is life on some planet outside the solar system (by deducing, say, a particular unstable mixture of gasses in its atmosphere that we can’t account for except by life), and that we are not investing nearly enough resources (money) in building the just-now-becoming-possible huge honking telescopes that would help us find such planets.
Or alternately, he says, it would also be extremely important in some way to discover that there isn’t life on any extra-solar planets that we can find, and that therefore we are even Specialer than maybe we thought.
There has recently been an Enormous Boom in the finding of planets outside the Solar System, apparently; an inneresting fact that I hadn’t known. Significant numbers of them are sort of vaguely Earth-like in various ways; also inneresting.
But, as I said during the Q-and-A period (for which I may appear on the YouTube at some point in the future!) I’m not sure how interesting it would really be to know that there is, say, probably pond-slime on Kepler 22b.
The two reasons the speaker gave for the importance of looking for extra-solar planets with life (besides raw coolness, which I don’t think is a good reason to spend billions of dollars, really) were (1) having more places for humans to live by the time the Sun swells up and eats the Earth or whatever, and (2) knowing whether or not We Are Alone In The Universe (hence the title of the book).
In terms of having more places to live, I think that by the time the Sun swells up (a few hundred million years), and even by the time we’re conveniently able to go in large numbers to other solar systems, we’ll long since have just remade ourselves so that we don’t need certain sorts of planets with particular chemistries to live on, so that particular issue will be moot.
And in terms of knowing whether or not we are alone, I think it’s far more important to know whether there’s anyone sentient out there than it is to know whether there’s any carbon-oxygen-based life out there. Given a few dozen billion dollars and the choice between looking for photosynthesis, and looking for intelligent signals, I’m going for the latter.
The extra-solar pond slime is just going to have to wait…
ceoln 
Hm?