Oh hello, all.

An update of sorts. Was at the New Mexico Museum of Natural History and Science the other day for a talk by Larry Crumpler, project scientist for the Spirit and Opportunity rovers, still very much involved in the exploration of Mars. He showed the image sequence below as an example of the changing surface features that may be due to current water -- or some other volatile -- flow. Larry mentioned that though "water" is the more or less generally accepted surface volatile, there are alternative ideas out there, one of them being CO2 flows. I thought that was very interesting, because Nick's ideas about CO2 surface flows seemed to be shot down long ago, and yet Crumpler seemed to be giving credence to the idea as an alternative possibility.

As many have said, the "water" hypothesis for Mars is problematical for all kinds of reasons. Doesn't mean there isn't or hasn't been water at the surface, but there are plenty of signs that what we think of as "water" -- a slightly saline solution at worst -- is not what has been available at the surface of Mars; more likely it's a strongly saline or acidic solution, quite nasty by terrestrial standards.

And the question of petroleum -- or something like it -- on Mars is still intriguing. At least at this point carbonates are quite certain, and carbon compounds including organics are not being automatically excluded from consideration as they once were.

Cheers,

BR