I remember an earlier post where I went lyrical over these amazing shots of small machines on another planet - and you reminded me that most of all, the MRO mission is really about geology. Well, this pic has it both, and with the advent of MRO I'm finding myself more drawn into the geology-for-its-own-sake. Martian features and textures really are amazing and bizarre (in the best sense), and those who see only an 'Earth-like desert' are simply not going beyond superficial first impressions. I'm ever more sure now, that people actually standing there would not experience anything much like Earth at all. Maybe they would even notice a few CO2-clathrate avalanches, who knows?