10 Apr 2009 17:40

The largest moon of Saturn. It's large enough to have its own, fairly dense, atmosphere, and really the only reason it's a moon and not a planet is that it orbits Saturn, rather than directly orbiting the sun. That atmosphere is why I'm interested in it: it is (or at least this was the theory about ten years ago) a very weird mix of nitrogen and hydrocarbons, with some evidence of a sea of liquid methane underneath. This is not just very bizarre, in its own right --- a sort of freezing smog --- but also very promising for the formation of complicated organic polymers. Of course, it's been ten years since I did any serious reading about this, in which time a lot, no doubt, has been learned...

Update, 21 January 2005: Huygens has landed. There are pictures. This is awesome.