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Breaking News: A NASA news conference is saying that the Mars Global Surveyor has found evidence that water has flowed on Mars recently.
Pretty exciting news!
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I hope it's true and not Carbon Dioxide. If it is. Then it would be another reason to go there.
"...all I ask is a tall ship, and a star to steer her by."
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Now if we point the SHARAD radar on MRO at this creator, then we potentially have the means of detecting any underground pockets of water that the flows might have come from.
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I hope it's true and not Carbon Dioxide. If it is. Then it would be another reason to go there.
CO2 does not become a liquid until the pressure is over 5 bar. On Mars the atmospheric pressure is way way below that. Solid CO2 directly sublimates to a gas when the temperature goes above -78°C and therefore it would not flow and disturb the surface as seen in the images.
[color=darkred]Let's go to Mars and far beyond - triple NASA's budget ![/color] [url=irc://freenode#space] #space channel !! [/url] [url=http://www.youtube.com/user/c1cl0ps] - videos !!![/url]
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I was excited about the news flash too.
And then a friend of mine pointed out elsewhere:
There's no easy way to break this to you guys, so I might as well 'fess up and get it over with.
I thought we were more or less at this point of understanding about water on Mars already.
I'd long since assumed from all the photos published since 2001 that water occasionally escaped from subterranean aquifers on Mars. It seemed obvious and I honestly didn't realize there was any serious doubt about it.
Did you? .. Really? :?
Yeah. Good point. :-\
We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...
--John Sladek (The New Apocrypha)
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Good.
I admit I wasn't expecting liquid water, but water vapor outgassing in the last decade was the only explanation I could ever come up with for the sharp, crisp gaps in this micro-imager photo from Purgatory Dune at Meridiani. That left a high albedo deposit behind, too, but you'll notice there's no evidence of flow as in the MSSS images. I fully expected our first water well on Mars would be a gas well or an ice mine.
Liquid water on Mars. I love it when Mars proves me wrong. 8)
"We go big, or we don't go." - GCNRevenger
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I hope it's true and not Carbon Dioxide. If it is. Then it would be another reason to go there.
CO2 does not become a liquid until the pressure is over 5 bar. On Mars the atmospheric pressure is way way below that. Solid CO2 directly sublimates to a gas when the temperature goes above -78°C and therefore it would not flow and disturb the surface as seen in the images.
"White Mars" explains that solid CO2 ("dry ice") can be maintained as a solid for two reasons: it is cold enough, and/or, the pressure on the solid CO2 is high enough. Thus, if there is a large block of dry ice under the surface, and it is loosen by a Marsquake, or the local tempersature rises a bit above critical, this can cause a conversion to liquid and gas CO2. The result can be explosive, causing a huge flood of liquid CO2 to course down a cliff face, or hill, ripping everything out of its way just like a torrent of liquid water.
See http://www.velocitypress.com/water_on_mars.shtml near the bottom for a bibligoraphy of articles on thisw subject. Fascinating reading.
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Thus, if there is a large block of dry ice under the surface, and it is loosen by a Marsquake, or the local tempersature rises a bit above critical, this can cause a conversion to liquid and gas CO2. The result can be explosive, causing a huge flood of liquid CO2 to course down a cliff face, or hill, ripping everything out of its way just like a torrent of liquid water..
The poles are very cold so CO2 stays solid even when it's on the surface. If the local temperature rose above -78 C it would vaporize, but complicated things can happen. Pockets of gas would increase the local pressure and liquid CO2 could form inside them, at higher pressure they could then explode and release that liquid. AFAIK quakes don't produce much thermal energy, nearly all the energy goes into deformation.
[color=darkred]Let's go to Mars and far beyond - triple NASA's budget ![/color] [url=irc://freenode#space] #space channel !! [/url] [url=http://www.youtube.com/user/c1cl0ps] - videos !!![/url]
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"White Mars" explains that solid CO2 ("dry ice") can be maintained as a solid for two reasons: it is cold enough, and/or, the pressure on the solid CO2 is high enough. Thus, if there is a large block of dry ice under the surface, and it is loosen by a Marsquake, or the local tempersature rises a bit above critical, this can cause a conversion to liquid and gas CO2. The result can be explosive, causing a huge flood of liquid CO2 to course down a cliff face, or hill, ripping everything out of its way just like a torrent of liquid water.
See http://www.velocitypress.com/water_on_mars.shtml near the bottom for a bibligoraphy of articles on thisw subject. Fascinating reading.
Hi Tholzel,
My understanding was that the theory was that there was frozen H2O permafrost, with liquid CO2 buried under it at enough pressure to be a liquid. If something caused the solid cap to break or vanish, the liquid would explosively boil. The vast amount of heavy gas lifting rock and sand would flow like a pyroclastic eruption, carving the channels that we see.
I doubt it however. The distances that the catastrophic floods covered seemed far too great for any sort of CO2 pyroclastic flow.
The White Mars theory was concidered pretty exotic, but it allowed channel type landforms with out resorting to liquid water. However, in the last 5 or so years Mars is proving a lot wetter than people expected.
This is not direct evidence that White Mars is wrong. But many people see less need to invoke it given that water is so common.
Warm regards, Rick.
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All the pictures that I have seen indicate that the polar caps are melting, and news articles back that up as well.
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Although it may be CO2, yet this discovery still add to the chance of life forms existing on Mars! We focus on water because water is the basis of earthly life forms. What if CO2 becomes the basis of life forms on Mars? They are both polar molecules and their movements transport chemicals from one place to another. We may even expect some simple kind of life built on Si rather than C as the situation is on Earth.
I am not a scientific worker but we can think outside the box, something may be there on Mars!
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