Titanic Lifeforms?

Have we perhaps seen the first signs of life on another planet - or at least a moon of a planet?

NASA/JPL has issued a press release suggesting exactly that. The Cassini spacecraft has been collecting data on the elemental composition of Titan, one of Saturn's moons. And what they have discovered could be interpreted in two ways....

The atmosphere of Titan seems to have less hydrogen than would be expected, and virtually no acetylene. The boring explanation is that some mineral or chemical on the surface has been catalyzing reactions that reduces the abundances of each. The more exciting possibility is that there is some form of methane-base life on the moon that is consuming the two substances.

A theoretical methane-based lifeform could use acetylene as a fuel source or food, comparable to plants on Earth taking minerals out of the ground. Such a lifeform could also breath hydrogen, leading to the reductions observed in the same way that animals on Earth consume oxygen.

Methane based life has never been observed on Earth, so if this is in fact a sign of life then it is a double discovery - both extraterrestrial and methane based. Of course a lot more research will be required to prove it is anything more than an interesting chemical reaction, but it does provide a fascinating possibility...