I promised myself that I wouldn’t start blogging again until my grades were turned in (by Friday of this week) and my book manuscript was sent off the the publisher (looks like that will happen in early January). But I couldn’t resist calling attention to this. It doesn’t have the most mellifluous name — GJ 1214b — but it is in important ways the most Earth-like extrasolar planet found to date. Lots of important and interesting things about this exoplanet, such as its orbital location placing it in the “habitable zone” surrounding its star, but the most important thing is that the planet appears to be composed of mostly water.
Yes, water. H20. One of the most basic building-blocks of life as we know it. And the density of this particular exoplanet strongly suggests that the planet is 3/4 liquid water, and also has an atmosphere of hydrogen and helium. Okay, granted, the atmosphere is like 10x thicker than ours, and the planet is hot and the surface is likely obscured by thick clouds and haze, so it’s not like we’ve found Twin Earth or something. But hey, at only 40 light-years out, it’s practically in our cosmic backyard, and it appears to have many of the elements that current scientific knowledge says are important preconditions for the existence of living beings.
So why does this matter? Setting aside for the moment any specific goals involving GJ 1214b itself (although I would be all for getting some kind of unmanned expedition together — launch it now, and in maybe a century and a half we’ll have some first-hand data on the place!), the real implication here is for something even more exotic: the probability of intelligent life elsewhere in the universe. The Drake Equation, widely used in exobiology as a way of estimating how many extraterrestrial civilizations there might be, rests on a number of parameters that have only speculative values; the discovery of exoplanets whose composition can be ascertained by observations made by Earth-orbiting telescopes might allow better estimates of some of those parameters. So we might have better estimates of just how likely — or just how unlikely — intelligent life is in the universe.
Either way, there are implications. Either we’re pretty darn unlikely, in which case we probably ought to think seriously about whether we should be continuing to waste our time as a species quarreling about small patches of terrestrial surface or imposing various ideas of the good life on one another at the point of a gun; or we’re pretty likely, in which case we probably ought to think seriously about why the heck we haven’t actually seen irrefutable evidence of extraterrestrial life yet — and my money’s on the zoo hypothesis, the notion that any alien species that detected us would cordon us off until we managed to mature a bit and in some sense demonstrate that we’re worth contacting.
But the point is that we have no way of knowing either way unless we get some better data — and GJ 1214b might be able to give us some. Think of the effect on global politics, on global life, if we were actually able to provide a scientifically respectable answer to the question “are we alone in the universe?” About the closest precedent that we have is the
discovery conquest of the “New World”; arguably, that changed basically everything. What kind of changes would be wreaked now? No way of knowing unless we head into that frontier and see what’s out there.
As the Starfleet motto has it: per aspera ad astra. Sometimes we should remember to lift our eyes and look beyond our often dreary political horizons; thanks to the astronomers at the Harvard-Smithsonian Center for Astrophysics, we have yet another exoplanet to dream on. And this one is likely full of liquid water. An ocean of possibilities; can we allow ourselves the conceptual flexibility to take advantage of them?