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Evidence For Liquid Water On a Frozen Early Mars
Matt_dk writes "NASA scientists modeled freezing conditions on Mars to test whether liquid water could have been present to form the surface features of the Martian landscape.
Evidence suggests flowing water formed the rivers and gullies on the Mars surface, even though surface temperatures were below freezing. Dissolved minerals in liquid water may be the reason."
Still valid, but this is not the question. They are trying to determine wether big bodies of water existed on Mars. About Mars having huge quantities of water ice, we know it from several years, we even have pictures of it and even a map of Mars' aquifers.
The Wise adapts himself to the world. The Fool adapts the world to himself. Therefore, all progress depends on the Fool.
Wow, another speculative article from someone one what COULD have been. I wish one of these days NASA would give me more than models, simulations, possibilities, and probes that are SUPPOSED to reveal actual conclusive evidence but which never do.
SJW: Someone who has run out of real oppression, and has to fake it.
Researchers did an experiment simulating the temperature and pressure conditions on Mars, and found that liquid water is possible because of the perchlorates Phoenix found on the soil.
http://www.universetoday.com/2009/05/26/more-researchers-say-liquid-water-present-on-mars-now/
But if there was salt in the water, there was probably also life in that water. Life living in the salty water making it saltier by pissing in it every single day.
The thinking that brines may keep the water on Mars from freezing is not a new conclusion-- here ( http://www.liebertonline.com/doi/abs/10.1089/153110701753198927?cookieSet=1&journalCode=ast ) is a discussion of the concept from a few years back.
And, of course, the fact that the Opportunity rover found the Meridiani Planum site to be covered with evaporite deposits (mostly sulfate salts) contributes a lot...
http://www.geoffreylandis.com
Is it possible that mars was warmer at a time? Either with a high level of CO2 or some other greenhouse gas that would have warmed the surface enough for running water?
Yes, that's a good summary of the current scientific thinking. The Viking orbital images show a lot of the surface is sculpted by water-carved features, and the belief is that Mars originally has a much thicker carbon dioxide atmosphere, which provided a significant amount of greenhouse warming (*). With the loss of Mars' magnetic field, this thick atmosphere was slowly eroded away by the solar wind to the very thin atmosphere we see today.
Maybe a little more dramatic but maybe even a slightly closer orbit?
No, that's quite unlikely. Planets are hard to move.
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*Footnote: The media likes to pretend that there is some controversy about the fact that carbon dioxide produces greenhouse effect warming (because controversy sells newspapers), but in the science community studying planetary atmosphere, there is no controversy whatsoever. It is just physics.
If you search hard enough, you can find somebody who disagrees, and quote them, and say, "look, not all scientists agree!" And since this is /. I'm sure somebody's about to do that: the miracle of the internet is that these fringe thinkers have just as loud a voice as people who have actually stufied the subject. But nevertheless, the greenhouse effect is just physics. And relatively simple physics.
http://www.geoffreylandis.com
It's been suggested recently that the perchlorates invalidated the micro-oven experiments, Apparently when heated they release large amounts of oxygen that would incerate any organics. Since I only have a vauge idea of what a perchlorate is, I have no idea if that's a valid criticisim. But given the possibility of ground water I think the methane hots spots are worth a closer look.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
The only problem I can see with all your comments is that you are assuming this took place a long time ago. We know that Mars can reach the mid 20s C and we also know that there are massive periodic dust storms.
Don't you think the storms would have eroded away the water gullies, or at least filled them with dust by now ? So I would say the formations are a lot more recent than "in the ancient past when Mars had a bigger atmosphere".
That's a very good question. But the problem is one of sublimation. That is from solid state to gas. It happens in cold dry air. Snowcap-free Mt Kilimanjaro in Al Gore's "Incon. Truth" didn't melt from global warming. It sublimated because farming on the windward side made the air passing over the mountain drier.
The only way to keep the liquid water around is to have a denser, wetter atmosphere.
The problem with storms filling in gullies is that the dust particles are very fine, and have to be since there's not a lot of gas to move them. Without moisture, it is hard to bond to other particles (static charge being the leading cause) so its hard to have some drift that won't be blown away at the next dust storm.
That being said, there is evidence of water percolating. This won't be able to make large new gullies, but it will help maintain the ones that are there. And in fact, we have no idea of the gullies that exist that are filled in by dust. I can only conclude that the gullies we see are stable features left over from a time long ago. The "last of the line" so to say.
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