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Probable Water Ice Sighted On Mars

Posted by timothy on Thu Jun 19, 2008 09:12 PM
from the pronounced-wooder-ice-in-philly dept.
CraftyJack writes "Bright white chunks in the trenches dug by the Phoenix Lander have disappeared, leading Peter Smith & co. to believe that the chunks were ice that has since sublimated."
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  • by Zosden (1303873) on Thursday June 19 2008, @09:15PM (#23868043)
    Is there oil?
      • by K. S. Kyosuke (729550) on Thursday June 19 2008, @10:09PM (#23868539)

        btw, I feel the need to mention that H2O ice doesn't sublimate, CO2 ice does.
        *Whoosh*! (That was the sound of all the world's freeze dryers [wikipedia.org] stopping working simultaneously...)
      • by JebusIsLord (566856) on Thursday June 19 2008, @10:10PM (#23868553) Homepage

        Yes it does and can, at low atmospheric pressures (such as there is on Mars).

      • by GeffDE (712146) on Thursday June 19 2008, @10:12PM (#23868567)
        H2O ice does sublimate. Here's an easy way to prove it. All you need is a freezer and an ice cube tray.

        1. Fill ice cube tray with water (liquid, H2O water) and put it in freezer.
        2. Go back in a day and mark the level of the ice in the tray.
        3. Return later (preferably at least a week) and marvel at how the ice is below the level marked.
        4. ???
        5. Profit.

        The ice was in the freezer the whole time, so it didn't melt (assuming the freezer was set correctly and continuously powered). Therefore, the solid water lost must have changed to water vapor.
        • by Anonymous Coward on Thursday June 19 2008, @10:28PM (#23868675)
          I thought that was from asshole roommates.
        • by Ihlosi (895663) on Friday June 20 2008, @03:02AM (#23870079)

          H2O ice does sublimate. Here's an easy way to prove it.

          There is absolutely no need to prove that.

          Just pull up a phase diagram of water (google is your friend), look at the lower-left
          corner (i.e. low pressure and low temperature), and what do you see ?

          A line where the solid phase borders on the vapor phase.

          And what's a phase transition from solid phase to vapor phase called ?

          Bingo. Sublimation.

          • by Anonymous Coward on Friday June 20 2008, @05:28AM (#23870745)

            Yes, that's the scientific way. Don't prove it for yourself, take someone else's word for it.

          • by Anonymous Coward on Friday June 20 2008, @05:54AM (#23870893)

            There is absolutely no need to prove that the Earth is the center of the universe, orbited by the other celestial bodies.

            Just pull up a Ptolemaic diagram (google is your friend), look at the center (i.e. within the orbits of the planets), and what do you see?

            A circle which is, in fact, the Earth.

            And what does the fact that the Sun and all other celestial bodies have concentric orbits around the Earth prove?

            Bingo. Geocentrism.

      • by hcmtnbiker (925661) on Thursday June 19 2008, @11:13PM (#23869011)
        btw, I feel the need to mention that H2O ice doesn't sublimate, CO2 ice does.

        And I feel the need to mention that Mars is not Standard Temperature and Pressure. The atmospheric pressure on Mars is about 1/100 that of Earth, I honestly don't know if that's reason enough for why H2O may experience sublimation like that, but I'm too tired right now to look it up and/or crunch some numbers and see if it does or not.
        • by Deadstick (535032) on Friday June 20 2008, @12:03AM (#23869261)
          The triple point pressure of water is 0.006 atmospheres, and that is based on the partial pressure of water on the gas side. The total pressure on Mars is about 0.008 atm, so the partial pressure of water in it would be much less than 0.006. Yes, water ice will indeed sublime (which is the preferred form of the verb in a physics context; "sublimate" is used in a sociological context).

          rj

          • by Fluffeh (1273756) on Friday June 20 2008, @12:57AM (#23869525)
            I still can't say that I agree on your point of view.

            Space exploration has no benefit for society in general.
            So there is no point in understanding why we have tides? What about how sunspots generate random levels of radiation that plays havoc with the radio broadcasts and communications that we use? What about looking into the area of space around our humble planet to see if there is an asteroid or comet heading right for us? Don't you think that these three points off the top of my head have some sort of benefit for society in general?

            As for the swearing, my point is that if it is used as commonly as in your original thread, it really does water down. I got absolutely nothing against colorful language. My point is if you put in too much color, the whole thing becomes a gaudy mess rather than a well accentuated splash here and there.
              • by pushing-robot (1037830) on Friday June 20 2008, @02:10AM (#23869837)

                Well, we could just build a bigger catapult on Mars, if only it had some sort of giant fucking mountain, we could build the mass driver along the side of it.

                Like this one [wikipedia.org]?

                You probably want something steeper, though.

                I'll refrain from making a reference to the relative spatial positions of you and the joke. ;)

                But escape velocity isn't really a velocity, as your trajectory is irrelevant. (Assuming it's, you know, above the horizon...) As long as you're traveling above a given speed, you'll escape the gravity well whether you're pointed straight up or towards the horizon.

                The reason we launch rockets vertically is to minimize the time spent in dense atmosphere. You get a lot of drag at low altitudes here on Earth, so it's better to climb quickly and get to where the air is thin as soon as possible.

                Mars is another story: Air pressure at the top of Olympus Mons is only ~0.003 that of Earth sea level. Launching a payload at a shallow angle through that would be no huge waste of energy.

                On the moon (or anywhere that lacks an atmosphere), you could lay the mass driver right down on the surface and it wouldn't make any difference.

  • by Gewalt (1200451) on Thursday June 19 2008, @09:15PM (#23868049)
    Haven't we known for a good many years that there was water ice at the cap?
    • by WaltBusterkeys (1156557) * on Thursday June 19 2008, @09:23PM (#23868121)
      Yes, we've even mapped the ice at the poles [nasa.gov]. But this is still important for a couple of reasons.

      First, it's confirmation that the white stuff at the poles really is ice (and not some unknown martian substance that just looks like ice).

      Second it means that the lander is digging in the right places to find all of the interesting stuff that goes along with water. It's tremendously interesting to discover whether there's carbon-based fragments in the water (suggesting life did or could exist) and to figure out what else is in the water.
        • by MarkusQ (450076) on Friday June 20 2008, @01:31AM (#23869679) Journal

          Sorry if it sounds like I'm trolling, but I just can't understand our push into space. Maybe it's the engineer in me, but if we can't exploit it (or learn something exploitable from it), why pursue it? It's not that it's not interesting (even fascinating), but not particularly useful as far as I can see.

          You're right, it does sound like you are trolling. But I'll bite.

          First off, you are aware that one of the best ways to improve your national engineering cadre (and thus, your economy, standard of living, etc.) is to attempt things that are at the border of your capabilities, or even just a tad beyond, aren't you? Even if the only thing out there was a big brass ring that was way far away, it would pay to push your limits by constantly trying to grab it faster, or cheaper, or whatever.

          Second, you realize I hope that NASA's budget is minuscule in the big scheme of things; we spend much more on things like professional sports and junk food that are even less useful. Our entire space program from 1958 to today cost less than our current misadventures in the middle east.

          Third, did you ever stop to think about where the vast majority of the available resources are? From energy to precious metals to useful chemical to just plain space the overwhelming majority of the resources we know about are out in space.

          Given all that, it hardly seems sensible to deride the space program as useless.

          --MarkusQ

        • by mysticgoat (582871) on Friday June 20 2008, @09:00AM (#23872585) Journal

          Whether parent is a troll or not, the question raised deserves some kind of answer.

          Getting into space is not the long term goal.

          The long term goal is to get back into The Garden. The way to do that is to move all the factories (and most of the engineers) into space. This is all spelled out in the Ecological Manifesto. Which you can find written in the reflection of the clouds on any stillwater lake where you've got solitude surrounded by a few acres of wilderness.

    • by NMerriam (15122) <NMerriam@artboy.org> on Thursday June 19 2008, @09:34PM (#23868225) Homepage
      Indeed, we've known this for several presidential administrations:

      If there is water, that means there is oxygen.

      If oxygen, that means we can breathe.
        • by pokerdad (1124121) on Thursday June 19 2008, @09:57PM (#23868457)

          Only if you separate the oxygen from the hydrogen first. That takes energy. Since the atmosphere is mostly carbon dioxide you might as well plan to split it into carbon and oxygen.

          I'm pretty sure the poster (and anyone else who would be browsing slashdot) knew that; the quote is from Dan Quayle, he's the one who needs help.

  • Rubbish. (Score:5, Funny)

    by jd (1658) <imipak.yahoo@com> on Thursday June 19 2008, @09:16PM (#23868061) Homepage Journal
    The white things were Martian beach loungers. And as they were there first, I strongly suspect they were German-speaking Martians.
  • by Bandman (86149) on Thursday June 19 2008, @09:17PM (#23868073) Homepage
    Excellent. Some coke and rum and we've got ourselves a party!
  • Dry ice? (Score:4, Insightful)

    by zygotic mitosis (833691) on Thursday June 19 2008, @09:21PM (#23868103)
    In such a carbon dioxide rich atmosphere, how do we know it is water ice and not frozen CO2? What do we know of the Martian surface and subsurface temperatures?
  • by oskard (715652) on Thursday June 19 2008, @09:22PM (#23868105)
  • by putaro (235078) on Thursday June 19 2008, @09:34PM (#23868221) Journal
    We often see the scientific community putting manned spaceflight down, saying that it is not useful for scientific research. Had we sent people, with even a minimal laboratory, we'd have known within about 15 minutes whether what they were digging up was ice or not. Since the lander doesn't have an "ice" experiment/module on board, we're reduced to guess work.

    The reality is that manned spaceflight is not *economical* for scientific research at this point. We should be working on getting our launch costs down so that we could actually send people to do things, build factories in space, and start getting some real benefit out of space.
    • by CrazyJim1 (809850) on Thursday June 19 2008, @09:43PM (#23868301) Journal
      Come on please. It is easier to get stuff there than to get stuff there and return it. Maybe a robot isn't perfect in its science capabilities, but it is well armed with equipment. Robots are great to go dangerous people. Which do you think is better for science: A: Robot lander crashes, retry again in a few months B: Philip Fry crashes on moon and dies a death, are we ever going to try that again?

      And there is always C & D. C: Robot lander lands on Mars and completes mission. D: Philip Fry completes mission, but the return module will not leave Mars. Will we ever try that again?

      I'm a big fan of robots to do stuff like this.
      • B: Philip Fry crashes on moon and dies a death
        Oh! Had they only built the ship with 6000 and 1 hulls this would have been avoided. When will they ever learn?

        I agree though; this robot isn't as good as a human, but the folks at NASA are pretty bright. It's speculation now but after a few more tests they'll have the data they need for a solid conclusion. It's still very early in the lander's mission on Mars. We need to have a little patience.

      • by Bartab (233395) on Thursday June 19 2008, @10:09PM (#23868547)

        Come on please. It is easier to get stuff there than to get stuff there and return it.

        Find a couple astronaut capable people who have recently been diagnosed with cancer. Couple years to live, don't bring them back.

        A little cold hearted to design, but I'd guarantee you would have no lack of volunteers.

      • by Zadaz (950521) on Friday June 20 2008, @03:13AM (#23870135)

        Manned space flight is afraid of a few deaths? What evidence do you have?

        Gus Grissom, Ed White, and Roger Chaffee die during a ground test and we still landed on the moon 2 years later.

        Dick Scobee, Michael Smith, Judith Resnik, Ellison Onizuka, Ronald McNair, Gregory Jarvis and Christa McAuliff died in the Challenger explosion and we were back riding the same design to orbit 2 years later.

        We lost Rick Husband, William McCool, David Brown, Kalpana Chawla, Michael Anderson, Laurel Clark and Ilan Ramon in the Colombia reentry. And again, 2 years later we're back in space on the same vehicle.

        Just because you're too much of a wimp to risk your life doing something amazing and unique, don't condemn the rest of us to mediocrity.

    • by CraftyJack (1031736) on Thursday June 19 2008, @09:53PM (#23868407)

      the lander doesn't have an "ice" experiment/module on board
      TEGA [arizona.edu] has that capability. Verifying the presence of water ice is an explicit science objective [arizona.edu] of this mission.
    • by Narpak (961733) on Thursday June 19 2008, @09:55PM (#23868429)
      Not to mention discover better ways of maintaining the integrity of the human body. Apparently Zero Gravity isn't exactly reckomended for your health.

      The most significant adverse effects of long-term weightlessness are muscle atrophy and deterioration of the skeleton, or spaceflight osteopenia. These effects can be minimized through a regimen of exercise. Other significant effects include fluid redistribution, a slowing of the cardiovascular system, decreased production of red blood cells, balance disorders, and a weakening of the immune system. Lesser symptoms include loss of body mass, nasal congestion, sleep disturbance, excess flatulence, and puffiness of the face. These effects begin to reverse quickly upon return to the Earth.
      http://en.wikipedia.org/wiki/Zero_gravity#Health_effects_of_weightlessness

      I imagine that traveling to Mars and staying there to do serious research would, without significant advances, mean a shorter lifespan and for some; a martian burial.
  • We Blew It (Score:5, Funny)

    by Doc Ruby (173196) on Thursday June 19 2008, @09:54PM (#23868413) Homepage Journal

    After all this time and effort, we finally found water on Mars, and we let it get away!

  • Another article... (Score:5, Informative)

    by yorugua (697900) on Thursday June 19 2008, @10:02PM (#23868489)

    Another article about the same news: http://blog.wired.com/wiredscience/2008/06/mars-phoenix-tw.html [wired.com]

    There is water ice on Mars within reach of the Mars Phoenix Lander, NASA scientists announced Thursday.

    Photographic evidence settles the debate over the nature of the white material seen in photographs sent back by the craft. As seen in lower left of this image, chunks of the ice sublimed (changed directly from solid to gas) over the course of four days, after the lander's digging exposed them.

    "It must be ice," said the Phoenix Lander's lead investigator, Peter Smith. "These little clumps completely disappearing over the course of a few days, that is perfect evidence that it's ice."

    The confirmation that water ice exists in the area directly surrounding the lander is big and good news for the Martian mission. NASA's stated goal for the Mars Phoenix was to find exactly this -- water ice -- and then analyze it. With the latest news, the first step is accomplished. All that's left now is to get the water into the Phoenix's instruments, a task which has occasionally proven more difficult than anticipated.

    Still, this is the best opportunity that humanity has ever had to analyze extraterrestrial water in any form. That had the Phoenix Lander's persona fired up.

    "Are you ready to celebrate? Well, get ready: We have ICE!!!!! Yes, ICE, *WATER ICE* on Mars! w00t!!! Best day ever!!" the Mars Phoenix Lander tweeted at about 5:15 pm.

    Their suspicions about water ice beneath the surface of Mars confirmed, scientists and the world will have renewed interest in the outcome of the soil analyses currently being conducted by the lander.

    The samples are being examined for traces of organic molecules, among other substances, but the lander does not have instruments that could directly detect life.

    See the full announcement from NASA.

  • I think the most important thing, and it is something that everyone keeps missing, is that NASA has found a way to turn even rocket scientists into ditch diggers!
    Imagine a bright young engineer studying hard on saturday nights, while all his friends are getting drunk and laid, and thinking how he'll have a successful career with NASA. And when thinking about his lucky friends he says to himself "the world needs ditchdiggers too."
    And some day he gets into NASA, and his boss's first words are:
    "Johnson, this ain't rocket science, Phoenix has landed and I need you do dig me a ditch..."

  • Ice sublimes. (Score:4, Informative)

    by Dr. Mu (603661) on Thursday June 19 2008, @11:52PM (#23869211)
    Geeks sublimate.

    (Okay, okay, I just looked it up: "sublimate" can also be used with ice, but "sublime" is preferred.)

  • by KidSock (150684) on Friday June 20 2008, @01:00AM (#23869531)

    This time they really really really really really really found water. Just like the last time they really really really found water. But that one time they found water they really didn't. But this time they really almost definitely did.

  • WTF (Score:5, Insightful)

    by Phaid (938) on Friday June 20 2008, @04:05AM (#23870349) Homepage

    Jesus, I thought I signed onto slashdot, but after reading the comments I realize I must have clicked on Fark by mistake.

    • by MichaelSmith (789609) on Thursday June 19 2008, @09:56PM (#23868437) Homepage Journal
      I bet you could write about three thick books on that theme. You could pit a bunch of conservative geology types against power mad engineers with a small group of middle ground heroes in the middle

      But what would you call it. Something Mars. I know Red Mars, then the next book gets a slightly different name.

      The only problem is that the third book would probably run out of ideas about 10% of the way through.

      Maybe its not such a good idea to after all...
        • Re:co2 ice ? (Score:4, Informative)

          by sjf (3790) on Thursday June 19 2008, @10:08PM (#23868537)

          You are correct. I had not realized just how low the air pressure was on Mars: it can be around 0.006 atm which is exactly the point where ice will sublimate.
          Cool. Thanks !

          Why the f*ck was I moderated troll ? I was wrong, but trolling ? Sheesh, get a life.

    • by nicklott (533496) on Friday June 20 2008, @02:41AM (#23869973)
      You, sir, are a pedant. When I get up every morning I don't know that my dog is really my dog and hasn't been stolen overnight and replaced with a very clever mechanical copy. I can't really check without dissecting him and that tends to upset both of us, so I assume that it being highly improbable that burglars would have replaced my crappy dog with a very expensive robot he is still my dog. It makes life much simpler.

      Likewise we know there is ice on mars, and one of the very few ways that a solid lump can disappear without trace is for it to sublimate. Other ways are for something with long limbs to have reached over and picked it up or perhaps they were iron rocks attracted by passing magnetic clouds, or perhaps a tiny blackhole opened for just long enough to remove those pebbles. However we've pretty much proved conclusively that there is no long-limbed life on Mars and every other way is vanishingly improbable so Occam's razor tells us that it is likely enough that this is ice that we can, on website designed for popular consumption, dispense with the endless qualifiers.