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Mars Space Science

Evidence For Liquid Water On a Frozen Early Mars 63

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."
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Evidence For Liquid Water On a Frozen Early Mars

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  • Whatever happened to the "looks-like-a-liquid" that was evaporating from the soil where one of the rovers was scraping?
  • Warmer? (Score:3, Interesting)

    by mc1138 ( 718275 ) on Thursday May 28, 2009 @09:03AM (#28122375) Homepage
    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? Maybe a little more dramatic but maybe even a slightly closer orbit?
    • Re: (Score:3, Insightful)

      by drinkypoo ( 153816 )

      If Mars had a significant amount of water it almost certainly also had an atmosphere, which retained heat.

      • by mc1138 ( 718275 )
        Ding ding! Look at Venus for example, its atmosphere makes it hotter than Mercury even though its farther from the sun...
    • by Geoffrey.landis ( 926948 ) on Thursday May 28, 2009 @09:50AM (#28122959) Homepage

      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.

      -----
      *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.

      • No, that's quite unlikely. Planets are hard to move.

        Not so fast. :-) We have to look at the orbital decay to figure that one out. If Mars has to much velocity for its orbit, it'll work farther out. If it has too little velocity, it'll fall in.

        Combine that with tidal forces of the planets and the asteroid belt, and you might have a measurable affect.

        The key to moving mountains (and the planets they are on) is a very small force, over millions or billions of years.

        ---
        *Footnote: The greenhouse effect is well documented in the lab under ideal conditions (in seal

        • No, that's quite unlikely. Planets are hard to move.

          Not so fast. :-) We have to look at the orbital decay to figure that one out. If Mars has to much velocity for its orbit, it'll work farther out. If it has too little velocity, it'll fall in.

          Well, sort of. It won't "work its way out": if a planet has too much velocity for a circular orbit it will be in an elliptical orbit (it won't "work its way" into an elliptical orbit-- it will be in an elliptical orbit). However, if you work out how much energy that takes to move the planet, the number is, uh, extremely large. Planets are hard to move.

          Combine that with tidal forces of the planets and the asteroid belt, and you might have a measurable affect.

          Indeed, you "might." Turns out, however, that the perturbations do add up, but they don't add up enough to a large enough effect to significantly affect t

    • Re: (Score:3, Interesting)

      by scorp1us ( 235526 )

      The atmospheric composition of Mars is predominantly CO2 (95%). If you take some eco-nut stance, the warming is linear, if you take a better-modeled stance you'll find it is less than that. (Diminishes logarithmically)

      The real question is one of geology. Was Mars' inner core capable of producing a protective magnetic should like the Earth's? Remember Mars is smaller and will therefore cool faster. Our core, as the theory goes is made by counter-rotating spheres of liquid iron. With this, comes a thick, rich

      • Re: (Score:3, Interesting)

        by mc1138 ( 718275 )
        That's a good point about the core of the planet, I remember reading that only the Earth has the protective magnetic field. Is it possible, and this will draw on my real lack of geology, but would a shift in orbit, say a collision that formed the "moons" of Mars pushed it out, and had enough either change in temperature of maybe a collision itself was disruptive enough to stop it from working?
        • by Shakrai ( 717556 )

          I remember reading that only the Earth has the protective magnetic field.

          The gas giants all have them too.

          • by mc1138 ( 718275 )
            You're right, but I don't really imagine that we'd see water flowing through valleys on any of them...
      • OPINION: There is enough evidence to suggest that Mars could have been roughly equivalent to tropical - humid and warm. Weather or not its breathable is a whole other story with all that supposed methane...

        The pressure and temperature matter more than whether you can breathe the atmosphere without a mask. But maybe I'm just biased towards a rapid terraforming model :)

      • Re: (Score:2, Informative)

        by TapeCutter ( 624760 ) *
        "Weather or not its breathable"

        Somewhat ironically, life is what made our atmosphere breathable. Without life it's highly unlikely there would be anything more than trace amounts of free oxygen in an alien atmosphere.
      • Re:Warmer? (Score:4, Interesting)

        by smoker2 ( 750216 ) on Thursday May 28, 2009 @10:37AM (#28123583) Homepage Journal
        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".
        • Re:Warmer? (Score:4, Informative)

          by scorp1us ( 235526 ) on Thursday May 28, 2009 @11:36AM (#28124387) Journal

          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.

        • Re: (Score:3, Informative)

          ...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".

          The cross-section weighted average particle size of the dust particles is about 5 microns. Think of the particles as being ten times finer than the particles that make up talcum powder. It's more like cigarette smoke than it's like sand; it's not very abrasive, and doesn't do much in the way of erosion.

          Sandstorms, like we have on Earth, do much more erosion.

          However, yes, burial and deflation of features is a well-known effect on Mars. In some places the ancient surface is exposed, but in other places i

    • Doesn't Mars already have absurd levels of C02?
      • by mc1138 ( 718275 )
        Yes and no. It's atmosphere is something like 95% CO2, but the atmosphere is very thin. So what they have is mostly CO2 but they don't have very much.
  • We've so many things to learn from our red neighbor. I hate to put my tin foil hat on this early in the day, but I oft wonder how much data has been retrieved/analyzed/hypothesized upon that we (mouth breathers at-large) have not been made aware of. There are some tantalizing possibilities with Mars, both to learn of our past and to help forge our future. Like Buzz Aldrin, I think whomever the first Mars pioneers wind up being, they should not plan on returning...

    Without giving the scientific method a nod,
  • by elrous0 ( 869638 ) * on Thursday May 28, 2009 @09:06AM (#28122415)
    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.
  • Give this people eyre!

  • Let's just send some water over there and call it quits and go to Io, Europa or Ganymede

  • "We found that the salts in water solutions can reduce the melting point of water, which may help explain how liquid water existed in a frozen Martian environment" -- Alberto Fairen, a space scientist at NASA Ames Research Center, Moffett Field, Calif. and the lead author of the study.

    Scientists concluded that salty liquid water on Mars may explain the stability of fluids against freezing on the Martian surface at temperatures below 0C

    No! Really? That's completely well... unsurprising...

    I always

    • by mbrod ( 19122 )
      I've wondered the same. I would like to think it is just because the budget to do the real stuff just isn't there.
    • In college( 40 years ago) we poured the salt shakers into the ice water and then stuck the glass on a pat of butter to bond it to the trays.
      I don't find the speculation very interesting or new, either, and I will add that since they have no complete knowledge, and a way to verify, the planet could have been covered in fudge and cellophane.
      More scientifically, I could say that there are so many dimensions in the NULL space of that matrix that selecting one of infinite possible vector solutions is just silly
    • I guess if in a salaried environment and 'not nitpicking and actually having something useful to say' were built into a package you'd say something more useful than the above.
  • Somebody needs to get those guys at NASA a glass of water already.

  • by BigHungryJoe ( 737554 ) on Thursday May 28, 2009 @10:36AM (#28123569) Homepage

    I'm not going to see any Mars terraforming efforts in my lifetime, am I?

    That sucks. Why are we so slow?

    • 'Cuz those MPAA bastards at Paramount won't release the schematic to the fucking Genesis device. Sons of bitches! I could be drinking margaritas at the foot of Mons Olympus by now.

      At least briefly anyway.

  • by Anonymous Coward

    Actually, the pivotal factor is the great flood. The truth is we (human beings) were created by God within a 7 day period etc etc... BUT the original home for us was MARS. Hence the drastically different life spans, physiological discrepancies (giants and other deviations)and the environment.

    Having completed this beta phase and learned some valuable lessons, God took the opportunity to launch His RC on Earth and implement the necessary changes to continue development (see changelog commonly known as bible

THEGODDESSOFTHENETHASTWISTINGFINGERSANDHERVOICEISLIKEAJAVELININTHENIGHTDUDE

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