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Mars Space Science

A Third of Mars Could Have Been Underwater 167

Matt_dk writes "An international team of scientists who analyzed data from the Gamma Ray Spectrometer onboard NASA's Mars Odyssey reports new evidence for the controversial idea that oceans once covered about a third of ancient Mars. 'We compared Gamma Ray Spectrometer data on potassium, thorium and iron above and below a shoreline believed to mark an ancient ocean that covered a third of Mars' surface, and an inner shoreline believed to mark a younger, smaller ocean.'"
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A Third of Mars Could Have Been Underwater

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  • by FungusCannon ( 1408259 ) <willy889@@@gmail...com> on Tuesday November 18, 2008 @09:43AM (#25801309)
    It's gonna be a pain in the ass to get one of those rovers up to 88 miles per hour.
    • Re:To prove it... (Score:4, Insightful)

      by Anonymous Coward on Tuesday November 18, 2008 @10:25AM (#25801813)
      Wait until we find signs of human civilization there and discover they made a last ditch effort to escape their destructive lifestyle by migrating to a new planet they called Earth.
      • Re: (Score:3, Interesting)

        by harry666t ( 1062422 )
        Interesting hypothesis.

        I have recently read a book that was supposedly written by an alien. He claimed that: the Moon is empty inside and is a home to a race of living beings that are on a very high level of spiritual evolution, the global warming is caused solely by the sun (and the other planets of the solar system are warming up too), that there was a very advanced (more advanced than ours, both technologically and spiritually) civilization on Earth millenia ago, that vanished due to a world war in which
        • by tmosley ( 996283 ) on Tuesday November 18, 2008 @11:30AM (#25802807)
          My son, I welcome you to into the fold of scientology.

          ALL HAIL XENU.
        • Re:To prove it... (Score:4, Interesting)

          by geckipede ( 1261408 ) on Tuesday November 18, 2008 @11:52AM (#25803195)
          "My opinion: even if this is bullshit, every good lie has a kernel of truth in it." The only thing with even a ghost of truth in that is that you can measure the sun's contribution to global warming by looking at temperatures and/or reflected light from other worlds. This has been done. The sun's output is very close to constant.
        • I have recently read a book that was supposedly written by an alien. He claimed that: the Moon is empty inside...global warming is caused solely by the sun...advanced civilization on Earth millenia ago...terraforming technology...constant danger from alien races that would want us dead...weapons that could destroy souls...Galactic Union...US government is planning a *fake* "alien invasion".

          This is the craziest thing I ever read. Everyone knows the scientific consensus is that global warming is caused ent

        • Re:To prove it... (Score:4, Insightful)

          by sorak ( 246725 ) on Tuesday November 18, 2008 @01:58PM (#25805903)

          How much terraforming would you have to do to remove all evidence of an advanced civilization and a world war?

          If a nuclear bomb went off in New York City, and we wanted to pretend there was nothing there, we would have to knock down every building, melt down the metal, and place it back in the ground, find some way to convert plastics back into petroleum, plant a forest over the entire city, remove all the pollution and radiation from the air, dig up every corpse and remove items such as cell-phones, watches, and anything that is not biodegradable. Now, imagine doing this, with every city in the world...

          Couldn't they come up with a simpler cover story that allowed for an advanced civilization to wipe themselves out? Honestly, my point is that, for most notions, such as this, you have to ask yourself, how much effort, control, and sheer genius would be needed to hide a secret this big, and then ask, what are the odds of someone pulling it off?

          • Yeah, I have noticed many small inconsistencies across the book by myself. For example: TSA (The Supposed Alien) enumerates twelve stages of spiritual evolution, from primitive bacteria to uniting with what could be called "god" (humans are supposedly on the 4th stage - they are able to think abstractly and create a civilization). The next stage would be becoming aware of the reincarnation, having all the memories of the past lives back, becoming able to contact what TSA calls "the Universe's Memory" - a sp
        • Re: (Score:3, Insightful)

          He claimed that: the Moon is empty inside

          How does he account for the gravity?

          • Well, I think that if they have mastered things like interstellar travel or telepathy, are remembering their memories from the previous lives, and are in almost every single aspect technologically and spiritually superior from us, they would have some way of keeping the moon from imploding, keeping the mass/size ratio intact, etc., wouldn't they?

            Assuming they exist, of course.
            • Well, I think that if they have mastered things like interstellar travel or telepathy, are remembering their memories from the previous lives, and are in almost every single aspect technologically and spiritually superior from us, they would have some way of keeping the moon from imploding, keeping the mass/size ratio intact, etc., wouldn't they?

              So, ignoring all the "spiritualism" stuff, which is (as yet) scientifically unprovable and therefore pointless to bring up in a discussion involving questions of sc

              • Implosion is a non-issue because anyone who's taken basic physics or calculus can figure out that all gravitational forces cancel out inside a uniform hollow sphere.

                No.

                While the gravitational forces will cancel out at the very inside edge, that doesn't actually matter... that inside layer is still being squeezed by the weight of all the other layers above it, and the whole thing will collapse if it can't handle the pressure.

        • by kklein ( 900361 )
          ...These are sarcastic mod points, right?
        • Sounds reasonable.

        • I love me a good crazy conspiracy science "fiction" book. Why are you making us ask for the name instead of just giving it to us to begin with?

        • by syousef ( 465911 )

          I have recently read a book that was supposedly written by an alien.

          Tom Cruise?! I had no idea you posted on slashdot!!!

    • Re: (Score:3, Funny)

      by Anonymous Coward

      Never mind that, just try getting 1.21 jiggerwatts out of those solar panels.

      • One point twenty one jiggawatts!?! That'd take a lightning strike! They don't have many of those on Mars... or clock towers, for that matter.

    • Not really. Where they're going, they don't need roads.

  • by Anonymous Coward

    Scientists studying spacecraft images have a hard time confirming âoeshorelineâ landforms, the researchers said, because Mars shorelines would look different from Earthâ(TM)s shorelines. Earthâ(TM)s coastal shorelines are largely a direct result of powerful tides caused by gravitational interaction between Earth and the moon, but Mars lacks a sizable moon. Another difference is that lakes or seas on Mars could have formed largely from giant debris flows and liquefied sediments. Still ano

    • by blueg3 ( 192743 )

      The planets are getting closer to the sun, but not nearly fast enough to be interesting.

      • by Thanshin ( 1188877 ) on Tuesday November 18, 2008 @10:04AM (#25801557)

        > The planets are getting closer to the sun, but not nearly fast enough to be interesting.

        You mean interesting as in "Hmmm, we might want to have some means of space exploration in the next century at the latest" or interesting as in "My hair is on fire! My hair is on fire!".

        • by SBacks ( 1286786 ) on Tuesday November 18, 2008 @10:31AM (#25801885)

          You mean interesting as in "Hmmm, we might want to have some means of space exploration in the next century at the latest"

          A century is a very short amount of time on the solar timeline. The Earth won't fall into the Sun for 5 billion years or so, and even then, the Sun will have lost enough mass that models predict the Earth may be flung off into deep space rather than falling into the Sun.

          The more immediate concern is that over the next 1 billion years, the luminosity of the Sun will increase about 10% or so, which should be fairly devastating to life on Earth. But, thats due to the Sun getting older, not the Earth getting closer.

          • by c0p0n ( 770852 )
            Methinks 1 billion years is slow enough for life to slowly adapt, and habitats to change, to the new conditions; I don't see what devastation could happen because of this (apart from progressive change).
            • by cnettel ( 836611 ) on Tuesday November 18, 2008 @11:06AM (#25802317)

              At some point we have massive evaporation, which would tend to go catastrophic, i.e. Venus (water vapor is extremely potent as a greenhouse gas). A temperature above which proteins in most organisms coagulate would bring us down to archea. Photosynthesis in its current form also prefers lower temperatures. We know very little of what situations complex multicellular life can really adapt to, but we can say that Earth would no longer be within the range that we consider to be habitable when we do armchair analyses of exoplanets.

              It's not life as we know it, Jim.

              • Indeed. Depending on the situation though (and how advanced we are, if we're still around) we might be able to move our civilization off world. Mars will be getting warmer too. Combined with some terraforming (mainly to thicken the atmosphere and augment it's oxygen capacity), it might be habitable for a good bit longer than Earth. The lack of a magnetic field COULD be a problem though. I'm sure Mars gets less solar radiation than Earth at it's distance, but it receives a similar amount of cosmic radia

          • Yes, we are all concerned that in 1 billion years it will get 10% hotter on the earth. Let me stock up on sun-screen in case the my local grocery store runs out.

          • A century is a very short amount of time on the solar timeline. The Earth won't fall into the Sun for 5 billion years or so, and even then, the Sun will have lost enough mass that models predict the Earth may be flung off into deep space rather than falling into the Sun.

            I just wanted to expand on this to add a bit more perspective. We're talking about something that might happen 5 billion years from now. The Earth itself isn't even 5 billion years old (it's estimated at 4.5-4.6 billion years old).
          • by thelexx ( 237096 )

            "The Earth won't fall into the Sun for 5 billion years or so, and even then, the Sun will have lost enough mass that models predict the Earth may be flung off into deep space rather than falling into the Sun."

            Possible, but unlikely.

            This is a good article that mentions that theory: http://www.space.com/scienceastronomy/solarsystem/death_of_earth_000224.html [space.com]

      • And Mars is further from the Sun than Earth is, so if getting closer was the problem then we would have a much larger version of the problem already.
    • Re: (Score:3, Informative)

      by JerryLove ( 1158461 )

      Whatever caused the devastation on Mars, could be avoided on Earth with the correct approach to discovering the truth.

      Mars is devistated?

      Mars has no water/atmosphere because A)It is small and B)It lacks a magnetosphere (which is because its core has cooled which is 1) because it is small and 2) because it lacks a large moon). With no pressure, water sublimates. With no tectonic activity to introduce more, and less gravity to attract more from space, it dried up. Distance+no greenhousing also means its cold.

      For the reasonable future, Earth has none of these problems. Our current threat is "random catastrophy" or "runaway g

  • Yes, but... (Score:3, Funny)

    by verbalcontract ( 909922 ) on Tuesday November 18, 2008 @09:45AM (#25801325)
    Yes, but what percentage of Mars was covered with buggalo [wikipedia.org]?
  • Potassium Salts (Score:5, Informative)

    by praedictus ( 61731 ) on Tuesday November 18, 2008 @09:53AM (#25801421) Journal
    Makes some sense to see potassium anomalies in the old basins if there was water there which has since been evaporated, with the concentration increasing toward the centres, as potassium salts are somewhat more soluble than their sodium equivalents, theyd be the last left to precipitate out. Thorium on the other hand is usually residual, at least here on Earth, and tends to concentrate along shorelines and riverbeds due its high density and low solubility.
  • Dross (Score:2, Interesting)

    by zoomshorts ( 137587 )

    We are living on dross, http://en.wikipedia.org/wiki/Dross the impurities on the surface of a molten ball of nickel/iron
    that takes billions of years to cool, geologically speaking.

    Global cooling is the long range prognosis for us, just as Mars. Mars gets less solar power, being more distant from the sun.
    Mars HAD an earth-similar composition 2 billion years ago. It is what the Earth will look like in the future. Deal with it.

  • .Did they serve Pina Coladas at the beaches?
  • Check out Google Mars!

    http://www.google.com/mars/ [google.com]

    How cool is Google?

    • Re: (Score:2, Funny)

      by BenphemeR ( 1301865 )
      meh, it's just the same image over and over. Zoom all the way out.
      • Is that a joke?

        I'm fairly certain that if you looked at the Earth and kept panning east or west, you'd see the same image over and over. Try it with Google Maps. [google.com]

  • I mean... what difference does it make that mars once had liquid water? It doesn't now. Sure... discovery of liquid water _still_ being on mars would be a big deal because it would drastically simplify the process of human beings staying there for extended periods in possible future missions, but if Mars was once covered in water, and isn't anymore, what difference could this possibly make to us?

    The argument that understanding the way Mars once was helps us understand ours own planet a lot better seems

    • Re: (Score:2, Insightful)

      The reason the people are researching this is intellectual curiosity, and for the grant money that pays the scientists bills. This information may or may not have any use to anyone alive today, but it is a part of the puzzle of how the universe works. Perhaps in the distant future, this information and countless other data points will help humanity solve some problem. Or it may be just a useless piece of trivia. The point is, we do not, nor can can we know what things we learn about our universe will be

    • Two sides to this. (Score:3, Interesting)

      by jd ( 1658 )

      First, as others have noted, there is a massive level of sheer scientific curiosity. Prior to this, we didn't know of any planet other than Earth that ever had liquid water on it. We had no idea if such planets were rare or common, or even how to identify them if the water wasn't extremely visible and obvious. This allows us to know so much more about planets and their evolution in early solar systems than we ever knew before.

      Then, there is another side. Water, particularly if it is mildly acidic, leaves op

  • Why controversial? (Score:5, Interesting)

    by Tacubaruba ( 553520 ) on Tuesday November 18, 2008 @10:29AM (#25801865)
    Haven't we gotten past the point where the idea of Mars once having lots of water is controversial? I mean, it seems as if every new piece of evidence points in that direction, so what exactly still makes it controversial?
    • Re: (Score:2, Insightful)

      Why controversial in the first place? Was there strong evidence that water never existed on Mars before? This is science, not religion. We believe whatever the data indicates, and if we are proven wrong, no biggie, science is served either way.
    • by jmichaelg ( 148257 ) on Tuesday November 18, 2008 @01:17PM (#25805029) Journal
      The question is why Mars would have oceans then and not now. Put water on the surface today and that which doesn't freeze will evaporate due to the low atmospheric pressure. The atmospheric pressure is low because Mars doesn't have that strong a gravitational field to sustain an atmosphere. So the question becomes, how did Mars ever manage to have an ocean in the first place? It's not likely that it was more massive earlier on so it's not likely to have ever had an earth-like atmosphere that recycles the water back to the oceans. Sans gravity, you don't get a steady-state atmosphere. Sans atmosphere, you don't get to keep your water. Bottom line - it's a problem full of paradoxes. Weird.
      • by Nadaka ( 224565 )

        It has to do with partial pressure of a gas in relation to the escape velocity of the planet. All planets loose their atmosphere given a sufficient amount of time. Having higher gravity slows this process because a smaller portion of the molecules making up the atmosphere have a vector of motion with a magnitude greater than EV that does not intercept another molecule.

        Earth still has its atmosphere not only due to its higher gravity, but also because it is still volcanically active. The release of gas from

    • by Kjella ( 173770 )

      On Earth, everywhere there's water there's life. That makes it controversial by implication, even though corrolation is not causation but since they're ignoring good science already...

    • It's impossible for that much water to just evaporate into thin air in 6000 years.
  • I believe that the Earth used to be an asteroid hurtling through space. It then collided with Mars(which used to be in the orbit close to where Earth is today) and killed all life on Mars knocking it far off into orbit where it is today. Earth was then left with the tiny bacteria or rna or something frozen in it. It was later warmed and thawed by the Sun and that's how life was started on Earth. Too far fetched?
    • Too far fetched?

      Yes...

      I believe that...

      Do you really? I actually really, REALLY hope not. "Playing with the idea" is alright (wrong, but nevertheless, alright), but actually believing it would be pretty sad.

      It's a cute idea, but it's so far out of the realms of possibility due to the basic physics of what you're describing, the positions and orbits of the planets as they are, and just everything we know about how our solar system formed.

      • Re: (Score:2, Funny)

        If cheesey sci-fi movies have taught me anything, you will not be spared by the true Martians that escaped when the collision hit.
    • by cnettel ( 836611 )
      Yes.
    • I have a different theory.

      Look at this picture (the distances are on a logarithmic scale):

      http://upload.wikimedia.org/wikipedia/en/0/03/SolarSystemUnmarked.png

      The distance between every Nth planet and the sun is always (a*(N**2))+(b*N)+c (I forgot the exact values of a,b,c but you can easily check this by yourself if you're interested), with one exception: the 5th planet between Mars and Jupiter, that has been (IMO) most probably destroyed.

      There are of course theories that civilizations could have existed o
  • All other planets are inferior potassium.

    • That made me laugh out loud! And snort milk out my nose. Well, not really. But I did laugh. Well, chuckled, anyway. If I had mod points I'd have modded you funny.
  • Seems that scientists are now certain of the existence of ancient oceans on Mars after one of the rovers found fossilized windsurfs and kiteboards, as well as oil rigs.
  • But now that it's in outer space it's managed to stay dry.
  • Only a third of the planet underwater doesn't seem so bad compared to Earth right now. Did they have to do a bailout?
  • Maybe it's simply that the planetary "habitable zone" shifts over the life time of a star. Early on when the star is larger and crazier the safe zone is further out. Once the star settles down in a long term stable state the safe zone shifts in to a more permanent position and the planet(s) in that zone then get the chance to properly develop life as we know it. While the planet(s) that have now moved out of the safe zone become colder and any water that formed on the planet moves to say, the poles, and any

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