Thursday, December 01, 2005
The Lost Oceans of Mars
This weeks issue of the journal Nature is packed with news of interest to the Astronomical community. Mars rates high on the list. Firstly, the MARIS radar array, which is seeking buried water, appears to have found ice in a mid-latitude crater. This could be remanants of water that once flowed through Valles Marineris. MARIS will start seeking water in earnest in the coming weeks.
Image Credit ESA
Also, the OMEGA spectrometer has found evidence of clays in the old uplands of Mars. While the Mars rovers and orbital reconnaissance have found abundant evidence of past water on Mars, it appears to have been acidic, which is not conductive to forming clays. The finding of clays in the oldest terrains suggest that at early periods, between 4.0-3.5 Billion years ago, Mars was warm and wet and somewhat Earth-like, then as Mars evolved the water became salty and acidic before disappearing.
In other news Hayabusa has almost certainly got asteroidal samples, but it's engines seem to be playing up, casting doubt on a return to Earth. There is also the first in-depth reports of the Titan mission, but these are all subscriber only (so no links). I'll try and summarise later on, but particularly interesting is that the aerosols in Titan's atmosphere are complex, nitrogen containing organic compounds.