Post by Chicago Astronomer - Astro Joe on Dec 8, 2006 4:46:06 GMT -6
"This is terribly exciting!" - The Bad Astronomer
Today at 10:00 a.m. Pacific time, NASA announced they had, at long last, found strong evidence of recent liquid water flows on Mars.
"Recent flow of water on Mars from subsurface deposits. Wow!"
Phil Plait
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The astronomy/space exploration community biggest hoax skeptic has been awed by the news of liquid water flowing on Mars. Although holding reservations for more hard data, he is acknowledging NASA announcement of compelling evidence of what has been inferred for some time now.
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"But how do we know they are water? The context is the key. Gullies indicate the flow of a liquid. Dust avalanches do occur on Mars, but not anywhere near these gullies. The morphology (shape) is important too. See how the gully breaks up as it flows down the slope? That also indicates a fluid flow. Finally, the color is an indicator, too. The light color is difficult to make on Mars. In trenches, most places where the surface dust is disturbed, and impact craters, the underlying layers are always almost always dark. This indicates a different process. Also, numerical calculations using models indicate that whatever caused these gullies flowed like water, not like dust or rocks."
How much water are we talking about? Maybe 5-10 swimming pools’ worth according to Ken Edgett, the scientist who has been working on these data. It would be a pretty quick flash flood, and, weirdly, in the low atmospheric pressure, the water would be boiling even at the low temperatures of Mars.
"So what does this mean? Well, we’ve known of frozen water on Mars for decades, and we know there was activity in the past. These new observations indicate that things are happening on Mars now, within the past few years. And whatever it is that’s happening, it’s releasing water onto the surface, which in turn means that there is water just below the surface of Mars, at least in some places.
Read the entire Bad Astronomer blog here:
www.badastronomy.com/bablog/2006/12/06/liquid-water-on-mars/
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I am pleased that Phil is as excited about this as I am, and great to read his insights into this NASA announcement.
Can't keep a good astronomer down, although many try... ;D