Water flow on Mars?

Apparently recently proven. Is there already a thread on this? If so, please direct me to it and kill this one. If not, please discuss.

Looks pretty likely, so far. No definite confirmation yet, though. I found this article, which says, in part:

If the rovers drove by a puddle or a small stream would it even notice it?

Actually, what I was referring to was some satellite imagery taken years apart that apparently show some kind of erosion differences/channeling. Story here. More here.

Given the very low air pressure on Mars, (about 6 millibars IIRC), could water exist in liquid form? Wouldn’t it boil away, even at Martian surface temperatures?

There’s some discussion over in MPSIMS: Water on Mars? Hip hip hooray! Really…
Much more detail at Bad Astronomy: NASA To Announce Major ‘Find’ On Mars

The pressure gets up to 10 millibars or so in the summer, when the southern CO[sub]2[/sub] cap has sublimed; possibly higher in some spots. It also gets warm enough that salty liquid water might last for a while on the surface.

The side-by-side comparison photos on the Dec 12th Astronomy Picture of the Day website (http://antwrp.gsfc.nasa.gov/apod/) make it very clear what all the excitement is all about.

[ur=http://www.theonion.com/content/node/54360]In related news . . .


Does anyone theorize that Mars in the past might have had a thicker atmosphere? Thick enough, maybe, to produce a greenhouse effect and higher surface temperature, so liquid water on the surface would be more plausible?

There’s conflicting theories on this, with some people thinking that it might have only been for a brief period early in Mars’s life, while others think that it might have persisted for a longer period of time.

Personally, I think that the folks who believe that Mars has spent most of it’s life cold and dry are correct, and that the “wet” Mars folks are victims of wishful thinking.

Having finally seen the pictures (thanks to the above link) I’m starting to come around to this conclusion. That is the evidence of water flow?! :dubious: If you asked me, I’d say it looks like a landslide or rockfall. Sure, it might have been caused by water, but I sure as heck wouldn’t be willing to stand up and a soapbox and scream “WE’VE FOUND WATER !!!” at the top of my lungs.