Earthlike Mars? Options

[glennwsmith]

All, I know this isn't the right place for this post, but I've looked around and can't find an appropriate, current UMSF forum (Doug, perhaps you could give me some guidance on establishing such) -- so here goes: I think a [the] new paradigm for Martian geology is rapidly coalescing, namely, that Mars is very much like the Earth in terms of the preponderance of water -- except that it is all frozen, and covered under a thin layer of dust/regolith! See, for example, this article:

http://www.skyandtelescope.com/news/41995902.html

Hence the "seepages" found in crater walls; hence the evidence of catastophic flooding -- the result of volcanism melting huge pockets of ice. And I am going to add my own wrinkle (probably not original): that the differentiation of Mars into a rougher southern hemisphere and smoother northern hemsphere represents something like Earth's Pangea stage, ie, the northern hemisphere is a vast frozen sea covered with a thin layer of ice.

[Phil Stooke]

The map is very nice - but look how it's suddenly taken up in the press as proof of an ocean. It is suggestive, but so was the previous work. The fact of mapping more valleys than past workers did does not by itself prove there was more water. To my mind, every valley identified here must be compared with good modern images to determine whether or not it is real. I'm not trying to put down the hard work of doing the mapping, but I don't trust watershed algorithms very much. They create their own reality.

Phil