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Mars NASA Space Science

Ice Cliffs Spotted On Mars (sciencemag.org) 83

sciencehabit writes from a report via Science Magazine: Scientists have discovered eight cliffs of nearly pure water ice on Mars, some of which stand nearly 100 meters tall. The discovery points to large stores of underground ice buried only a meter or two below the surface at surprisingly low martian latitudes, in regions where ice had not yet been detected. Each cliff seems to be the naked face of a glacier, tantalizing scientists with the promise of a layer-cake record of past martian climates and space enthusiasts with a potential resource for future human bases. Scientists discovered the cliffs with a high-resolution camera on the Mars Reconnaissance Orbiter, revisiting the sites to show their subsequent retreat as a result of vaporization, and their persistence in the martian summer. The hunt should now be on, scientists say, for similar sites closer to the equator. The findings have been reported in this week's issue of Science.

Ice Cliffs Spotted On Mars

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  • by Anonymous Coward
    Frosty cliffs
  • Mars direct? (Score:4, Interesting)

    by AHuxley ( 892839 ) on Friday January 12, 2018 @02:19AM (#55913275) Journal
    Is the ice in a good location to explore space from later?
    Send humans to Mars.
    Get them using the water with more space exploring supplies sent from earth.
    A nuclear reactor and rocket fuel factory.
    Extract water to create more rocket fuel.
    A Project Iceworm for Mars? https://en.wikipedia.org/wiki/... [wikipedia.org]
    • Send humans to Mars.
      Get them using the water with more space exploring supplies sent from earth.
      Extract water to create more rocket fuel.

      Well at least these are SpaceX's plans.

      • by AHuxley ( 892839 )
        What are the other plans? Protect the ice from all future use as national historical ice parks?
        • It would take centuries to even get to the point where this would be necessary. And once you get to Ceres at least, the source of water becomes a moot point.
          • It would take centuries to even get to the point where this would be necessary. And once you get to Ceres at least, the source of water becomes a moot point.

            It might be useful to set aside a portion of the ice for habitation. One of the problems with Mars is radiation; one proposed plan was to have a water shield between human habitation and the atmosphere. An Ice Cliff is a natural water shield. Drill a tunnel into the ice; build insulated habitation under the ice. Not only are you near easy access to water (and thus, also oxygen); you're also protected from radiation which could be one of the big killers on Mars.

            • I should add... it would be relatively easy to drill tunnels in ice (and what you remove is usable water); but also the ice itself would be a great insulator lowering heating costs.

            • I'd think that polyethylene would be even better - more hydrogen per unit of mass and volume, I believe? And building a base under the ice is what the US military tried in the 1960s in Greenland, and I seem to remember that they had lots of structural problems with that.
              • Polyethylene would provide better shielding for its mass, which is why it's good for spacecraft, but mass isn't that big of an issue for surface habitats. You actually want a lot of mass on your pressurized structures to help hold the roof down against internal pressure.

                • Or you could simply make the structure out of thick polyethylene and cover it up with dirt. You kill three birds with one stone.
            • Maybe as a very short term shelter, but look into some of the Project Iceworm experiments done with digging military bases into Greenland glaciers. Ice isn't stable enough for that sort of thing, especially when being warmed by a base carved into it.

              You might use water as shielding on the surface...fill plastic bags, stack them up over a supporting structure, let them freeze...but you'd probably be better off with sandbags.

        • I'd like to think that a species-level decision like this wasn't made by a random billionaire. We need to ensure that we don't contaminate our ability to learn (esp. since ancient extinct/hibernating life may be present, probably mono-cellular).

          • There's already a minute chance our space probes/landers/robots have already transported Earth based life to Mars.

          • I'd like to think that a species-level decision like this wasn't made by a random billionaire. We need to ensure that we don't contaminate our ability to learn (esp. since ancient extinct/hibernating life may be present, probably mono-cellular).

            The chances of that are almost zero. The chance of us discovering life, without sending people to look for it if it is there is almost zero. I'm all for contaminating as little as possible until we know for sure; but we shouldn't put off science because there is a tiny fraction of a percent chance that there is life on mars.

            • I'm not for putting off science. I am for having it run by scientists, sponsored by the government, who only care about not-fucking-this-up. Responsive to the public, public and thorough debate over what choices we make, etc. I am not for a for-profit company making those decisions on behalf of all of us.

              • I'm not for putting off science. I am for having it run by scientists, sponsored by the government, who only care about not-fucking-this-up. Responsive to the public, public and thorough debate over what choices we make, etc. I am not for a for-profit company making those decisions on behalf of all of us.

                I would prefer a publicly accountable, open and visible international multi-government ran approach to Mars exploration too. The problem is; very little is getting done that way. Nations are, by and large, are not very ambitious in regards to intra stellar exploration anymore. SpaceX does something else too- it makes the people dream and think big about space. It might even push the government to spend less on building military bases in Ruritania and funding half the world's net military spending and in

              • Unfortunately; compared to the last 60 years, the chances of us getting to mars *at all* are appreciably better if left in the hands of billionaires vs scientists/government :(

                The chances of NASA having the funding (political and financial) to do any kind of meaningful manned exploration of mars are nil.

                China? maybe, but .. not sure if that's better or worse.

    • Is the ice in a good location to explore space from later?

      No. It's a lot easier to explore space from Earth, where we already have everything we need.

      • No. It's a lot easier to explore space from Earth, where we already have everything we need.

        Indeed. Earth has the advantage of an already existing industrial civilization. Mars has a a rover and a slightly shallower gravity well.

        But there are even more shallow gravity wells in the asteroid belt, and plenty of water there as well. A single asteroid may contain more water than all the oceans of earth [space.com].

        Using Mars as a base for deep space exploration makes no sense at all.

        Colonizing Mars doesn't make much sense either. We would be much better off constructing O'Neill Cylinders [wikipedia.org] in solar orbit. We n

        • by AmiMoJo ( 196126 )

          Constructing something that large in solar orbit is much harder than living on Mars. You have to get all the materials up there, do a lot of construction in zero G and handle solar radiation.

          On Mars you can build factories and use local resources. No need to expend vast amounts of energy escaping a gravity well for a lot of your materials. Existing tech works well in gravity.

          Then when you are living there you don't need a closed system or imported water and air.

          • On Mars you can build factories and use local resources

            How local are these resources ? Can you land in a random location, start digging, and find useful amounts of all elements you need to build an industrial base ?

            • by Anonymous Coward

              On Mars you can build factories and use local resources

              How local are these resources ? Can you land in a random location, start digging, and find useful amounts of all elements you need to build an industrial base ?

              We can't even do that on Earth. So while that would be nice and convenient and all, I don't see why that should be a requirement instead of just dealing with the problem like we do currently.

              But even then, it could be argued that such resources are even "more local" on Mars compared to Earth.
              If you were to pick a random location on Earth, you have a 70% chance of that spot being in an ocean.
              Then assuming you make your save-vs-ocean savings throw, not all of the land on Earth you would have picked at random

              • We can't even do that on Earth. So while that would be nice and convenient and all, I don't see why that should be a requirement instead of just dealing with the problem like we do currently.

                On Earth we have an established transportation infrastructure, and many industrial sites spread out over the planet.

                If you want to kickstart a base on Mars, you need to focus on reducing the launch mass from Earth. Sending all your stuff to one site is going to be insanely expensive as it is. Having to build a few dozen sites across the entire planet, with a usable transportation network between them would be completely out of the question.

            • No, but you can orbit a satellite that can locate the largest metal deposits. [nasa.gov] (My god, it was hard to find that link through all the bullshit about Kerbal and Space Engineers.)

              • Interesting. I wonder how well it would work on Mars.

                But even if you can locate all the ores, the big problem on Mars would be transportation. There are no oceans and rivers, no suitable atmosphere for flying, and no roads or train tracks. Transporting resources from one side of the planet to the other, across the rugged terrain would be a huge challenge.

                • by Khyber ( 864651 )

                  It will work better on Mars, as there's far less atmosphere to screw with the data.

                  I heavily utilize ASTER and LANDSAT 7/8 all the time for materials prospecting here on Earth. I'd LOVE to be using these satellites on Mars. Check out the spots where you can find advanced Argyllic weathering occurring, and go fucking dig there.

                  Or just scan the garnet sand dunes that were found a few months back. I'd kill to get to see those spectral readings.

          • by ceoyoyo ( 59147 )

            You're willing to mine Mars for materials for a Mars base but to make an orbital habitat everything has to be lifted from Earth?

            You'd build O'Neil cylinders using moon or asteroid material. Actually transporting them would probably be less work than transportation on Mars.

          • The asteroid belt has plenty of local resources as well, and you don't have to get them out of a gravity well. The cost - not just in resources, but in cargo space - of propellant is the second biggest problem in space exploration after the sheer size of space. Eliminate the need to propel out of a gravity well, and you eliminate the vast majority of that cost.
            • No, you don't, because the majority of the cost is due to orbital mechanics. Asteroids tend to be in elliptical, high-inclination orbits, and those likely to contain significant volatiles are out in the main belt or further. Ceres, for example, would be a much more difficult colonization target than Mars (though potentially easier if you could refuel at Mars). With its extremely high propellant efficiency, low thrust ion thrusters giving it around 10 km/s of delta-v, the Dawn mission was only able to visit

        • by Ogive17 ( 691899 )
          Your link about water on Ceres says it's possible it has more fresh water than Earth, not more water than all of our oceans.

          The total volume of water on Earth is about 1.4 billion cubic kilometers, around 41 million of which is fresh water. If Ceres' mantle accounts for 25 percent of the asteroid's mass, that would translate to an upper limit of 200 million cubic kilometers of water, Parker said.

          • Your link about water on Ceres says it's possible it has more fresh water than Earth, not more water than all of our oceans.

            Oops. Sorry, I misread the page. But that still includes all the water in the ice sheets of Antarctica and Greenland. That is likely much more water than Mars.

        • But there are even more shallow gravity wells in the asteroid belt, and plenty of water there as well. A single asteroid may contain more water than all the oceans of earth [space.com].

          This didn't seem right to me, and it's not. Reading the very article you linked in to defend this assertion, the asteroid in question contains more FRESH water than all of the LAKES AND RIVERS on Earth. About five times as much fresh water, but only 1/7 of the total water combined. There is a lot of water in the Earth's oceans.

          This doesn't really affect your conclusions -- as you say, there is a lot of water available on some asteroids or various moons in the solar system that have much shallower gravi

  • He may consider sending a few gas guzling beaters to mars... you know warm the place up :)
  • maybe, just maybe, this Mr. Mars may have been in a similar situation as our globe and messed up climate-wise similar what is going on on our ball with the speculative point of no return which is not always controllable or fitting in people's brains very well that some ideas are not just very dumb but highly dangerous.

  • I'm curious. Ice has been found on Luna's poles (it may need some processing but it's there), so why does Mars seem to be the go-to place for human colonization? Luna would be far faster/easier to get shipments to/from Earth, much faster communication times, no waiting for optimal interplanetary distance windows etc.
    The ice being on the poles shouldn't be as much of a problem. Maneuvering a spacecraft to land on Luna's pole should be far less delta-V than landing it on Mars (I presume). The ice could be pip

    • Probably because of the dream of Terraforming, which is theoretically possible on Mars, but not on the Moon.

      And if you're just looking for a simple base to launch rockets, then the Earth is much cheaper and simpler.

    • by joh ( 27088 ) on Friday January 12, 2018 @05:54AM (#55913751)

      Because on the Moon the ice is at best in eternally shaded craters, buried as small crystal in the dust. Evidence even for this is inconclusive (there's hydrogen there, but it doesn't have to be water). Then the Moon has an unforgiving thermal environment with lots of sun and long dark nights. And then the Moon has no atmosphere, which means no protection against micrometeorites. And then Mars has an atmosphere of CO2 which gives you a source of easy accessible carbon. Also to land on the Moon you have to brake with engines and propellants all the way down while on Mars you have the atmosphere to do most of that for you. Also Mars is much more interesting to explore, since it had a wet and warmer past, so you can go and look for signs of past life instead of digging through dead dust on the Moon.

      And nothing of this is in any way new.

      • by Anonymous Coward

        Also don't forget that the moon is a harsh mistress.

    • Mars has an 25h day/night cycle.
      Moon has a 28day day/night cycle.

      Mars has 1/3rd of Earth gravity.
      Moon has 1/6th of Earth gravity.

      Mars has about +20C at the equator in summer ... and obviously down to -150 (or so?)C at the poles in winter.
      Moon has about +300C at the equator (and basically everywhere on the day sie) and about -200 or -250 on the night side.

    • Apart from the immense costs of your pipeline proposal, relying on such a thing for your water supply would be incredibly risky, and still limits you to locations along the pipeline and activities that can be supplied sufficient amounts via the pipeline.

      Landing on the moon takes more propulsive delta-v than landing on Mars, so payloads are more limited and costs of moving material are higher. The lunar ice is going to be in the form of icy regolith instead of deposits of nearly pure water ice, and the moon

  • Core samples (Score:4, Interesting)

    by John.Banister ( 1291556 ) * on Friday January 12, 2018 @05:01AM (#55913633) Homepage
    A one meter by 50mm core sample would mass about 2 kg. The navy has railguns now that can accelerate 10 kg to about 2.4 km/sec [wikipedia.org]. According to this Delta V map [imgur.com], delta v to reach low Mars orbit is about 3.8 km/sec. Considering that it wouldn't have to be built to withstand use in warfare, it might not be that much harder than what we've already achieved to build a railgun that could launch an ice core to low Mars orbit.
    • Re:Core samples (Score:5, Informative)

      by bjorniac ( 836863 ) on Friday January 12, 2018 @06:28AM (#55913829)

      A single shot device like a railgun cannot launch something into orbit. You need a second impulse to alter the trajectory to achieve orbit. The reason is that orbits close - they're ellipses (or circles). So with a single shot device you either launch something to infinity, or you have it crash back into the planet as its orbit intersects the point of origin.

      What you'd need in this scenario is either something to collect the sample already in low orbit, or a container with a thruster of some sort to force the trajectory into orbit. Either case increases the difficulty considerably.

      • by Nidi62 ( 1525137 )

        A single shot device like a railgun cannot launch something into orbit. You need a second impulse to alter the trajectory to achieve orbit. .....What you'd need in this scenario is....a container with a thruster of some sort to force the trajectory into orbit. Either case increases the difficulty considerably.

        You mean like this [wikipedia.org]? The idea is farfetched anyway, but it's safe to assume the core sample would be containerized anyway in the projectile from the rail gun, so you would just have to make the projectile and the thruster strong enough to change the trajectory.

      • Yes, I was expecting that something would need to be in orbit to pick it up. I was thinking that the difficulty of aiming to where it could be picked up would be less than landing something on Mars capable of lifting both itself and a core sample off the planet - that it would be easier to land a sample taking robot, a railgun and some casings than to land a rocket capable of return. The equipment capable of return could stay in orbit, where the delta v for return is less.
    • by asylumx ( 881307 )
      Why would I want to put an Earth ice core in Mars orbit? Or are you suggesting once we have presence on Mars we could use railguns to send cores to orbit for pickup?
  • Crampons: check
    Ice axes: check
    rope, ice screws, pro and harnesses: check
    clothing and helmet: check
    beer: check
    SpaceX Big Falcon: ....uh. Stand by Houston.

A physicist is an atom's way of knowing about atoms. -- George Wald

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