Methane monsoons may lash Titan

By Maggie McKee |

Brief but powerful monsoons of liquid methane may lash parts of Saturn’s giant moon Titan every few hundred years, suggest new calculations based on observations with the Cassini spacecraft. Astronomers also think they have observed thunderstorms growing and raining down on the moon.

Methane makes up about 5% of the Titan?s thick atmosphere and is thought to rain down to the surface and then evaporate back into clouds in a cycle similar to the water-cycle on Earth.

Indeed, observations with both the Cassini spacecraft in orbit around Saturn and the Huygens probe sent down to Titan in January 2005 seem to bear this out. They show dark, river-like channels carved into higher, lighter terrain and a round feature resembling a lake near the south pole.