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Mars Space Science

Mars May Have Been 1/3 Ocean 118

Posted by kdawson from the blue-planet-red-planet dept.
coondoggie sends in a snippet from Network World, as is his wont: "It's possible that a huge ocean covered one-third of the surface of Mars some 3.5 billion years ago, a finding likely to reignite an old argument about that amount of water on the red planet, according to a new report. The study by the University of Colorado at Boulder is the first to integrate multiple data sets of river deltas, valley networks and topography from a cadre of NASA and European Space Agency orbiting missions of Mars dating back to 2001, the researchers claim." The National Geographic coverage of the news gives some air time to those doubtful that this study will prove definitive.
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Mars May Have Been 1/3 Ocean More

Mars May Have Been 1/3 Ocean

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  • maybe it's time to enlist the Japanese (Score:3, Insightful)

    by ChipMonk ( 711367 ) on Monday June 14, 2010 @10:50PM (#32574560) Journal
    They just proved they can bring back material from an asteroid. Let's see if they can duplicate the feat on Mars.

    • Re:maybe it's time to enlist the Japanese (Score:5, Insightful)

      by JoshuaZ ( 1134087 ) on Monday June 14, 2010 @10:57PM (#32574596) Homepage
      We don't know if the capsule from Hayabusa does contain material yet. Also note that a sample-return mission to Mars will be much more difficult than a sample-return mission to an asteroid. The gravity of an asteroid is negligible. But Mars has gravity that is around a third that of Earth. That's a lot. So a sampling robot would need to land on Mars and then return fighting against the large Martian gravity well. It would probably need to carry its fuel with it which means it would need to have a lot of mass to start with and which would make a safe landing even more difficult. We'll probably have successful sample-return from Mars before a human mission their but the technical difficulty with even a sample-return mission is immense.

      •     Escape velocity, fuel supply, navigation. People always bring up those pesky problems. Gimme a spaceship that runs on dilithium crystals that you can run a starship at multiples of the speed of light indefinitely (or at least until the episode plot calls for them to be used up).

        • Re: (Score:3, Funny)

          by Hognoxious ( 631665 )

          Or attach it to a really long leash.

          [This post brought to you by the institute of cord spinners, rope braiders and string twisters]

      • Re:maybe it's time to enlist the Japanese (Score:5, Interesting)

        by symbolset ( 646467 ) on Tuesday June 15, 2010 @12:46AM (#32574990) Journal

        Update: it's been opened. It contains material. The report is due six months or so, so set a tickle.

        Mars is easier than an asteroid. At Mars you have a planet to cancel your Delta-V with its gravity and atmosphere (limited though Mars' atmosphere is, it does help). Hitting an asteroid and returning is roughly twice as hard as hitting Mars and returning because you have to halt your motion at the asteroid using propulsion. It's a miracle Hyabusa returned at all - and it was three years late - because it missed its return window and had to wait for Earth to come back into position. The efforts of the ground team could be considered heroic - if some blood had been spilled.

        • Re: (Score:3, Funny)

          by takev ( 214836 )
          Someone probably slashed their finger open on the inside of a computer case, dropping blood on the motherboard. So in all likelihood blood has been spilled by the ground crew.

        • Re: (Score:3, Insightful)

          by stevelinton ( 4044 )

          Getting to Mars is, in some was, easier than getting to an asteroid, because you can stop for free at Mars. Getting home again is much harder. There's no cheap way OFF Mars.

          • At least you can put most of your fuel in orbir around Mars. You only need enough on the craft to break orbit, which is still a fair amount, but nothing approaching the total load. Half the fuel typically used on a craft is there simply to lift the other half of the fuel.

            • Re:maybe it's time to enlist the Japanese (Score:4, Informative)

              by stevelinton ( 4044 ) <sal@dcs.st-and.ac.uk> on Tuesday June 15, 2010 @06:55AM (#32576326) Homepage

              Let's do the numbers.

              The ascent stage (ie the Mars to Low Mars Orbit transport) needs about 4.1 km s^-1 of delta-V. About twice what you need from the Moon, but less than half what you need from Earth. The Mars orbit return vehicle, which doesn't need to land on Mars needs about 2.3 km s^-1 to get into a transfer orbit back to Earth. (figures from wikipedia).

              This is definitely challenging, ascent stage most challenging of all. We need a rocket that can survive launch from Earth, 9 months coasting, aerocapture and aerobraking at Mars, impact with the Mars surface, a few months sitting on Mars and then take off with no support systems, deliver 4+kms^-1 of delta-V and automatically dock with the orbiting component of the system. The durability requirement pretty much rules out cryogenic fuels, and even relatively stable liquid fuels like kerosene/nitric acid might give trouble, both due to the cold conditions on Mars and the extra mass of tankage robust enough to survive the journey, so you're probably looking at solids.

              A few quick checks reveal that good solid rockets have an ISP of maybe 265s, giving a mass ratio of perhaps 10 for Mars to Low Mars orbit, so we need an ascent stage roughly 90% of which is solid rocket propellant (or multiple ascent stages, adding complexity). Suppose we can get the payload capsule + docking system down to 10kg and our solid rocket motors are 95% propellant (5% nozzles and casing -- this might be optimistic) we get a mass of 200kg launching from Mars. This is actually less bad than I'd feared. Seems that a Viking sized lander could probably do it. A 1 ton or so lander includes a digging tool and maybe a mini-rover to collect 5kg of rock and load them into a 5kg capsule with some tiny thrusters on it. That sits on a 200kg solid fuel rocket that gets into Low Mars Orbit and drops the capsule, which docks with a similar sized vehicle with 100kg of solid fuel some batteries and electronics and a heat shield for Earth reentry.

              So we need two launches to Mars transfer, each about 1 ton payload, plus heat shields for aero-braking/aero-capture on Mars. Should be doable as two medium large launches from Earth

              • Re: (Score:2)

                by blair1q ( 305137 )

                Or we could send a roving waldo with a mass-spectrometer on it, and get months or years' worth of data from tons of samples in an exhaustive, directed survey, instead of waiting an extra two years to have a few pebbles in-hand and no way to examine the rock they were sitting on...

                • Yes. And so far that's been the choice, but we could certainly do a lot more analysis of the pebbles back on Earth than anything we could do on Mars. With modern instruments we could come scarily close to listing every atom in the sample by isotope and position.

                  • I will have to trust your math, as I am certainly not a rocket scientist. It does seem that once you get rid of the human element (life support, food, water, recreation, etc.) you have gotten rid of 90% of your problems. Several people have talked about doing a mission to mars (manned or not) using multiple launch vehicles. It would seem you might as well put the craft that will fly back to earth in orbit only, and the lander having only enough mechanical to get into orbit and dock/load, ie: not needing

                    • Obvious steps along the road are to practice on the Moon (there are plenty of interesting parts of the surface we've never sampled and we can try as often as we want) and on Phobos and Deimos.

                  • Re: (Score:2)

                    by blair1q ( 305137 )

                    If by "modern" you mean "antique [wikipedia.org]".

                    I bet we could automate the process in a portable module that the rover could dump pebbles into from time to time.

              • Re: (Score:1)

                by nelk ( 923574 )
                We know that large impacts on Mars have transferred material to Earth in the past, and continue to do so. I say we just launch a ton of nukes a Mars and wait for the samples to come to us!

          • Re: (Score:2)

            by Gilmoure ( 18428 )

            What about setting some nano-replicators loose on Phobos and have them build a beanstalk down to Mars?

            Oh, wait, what century is this?

        • Mars is easier than an asteroid. At Mars you have a planet to cancel your Delta-V with its gravity and atmosphere (limited though Mars' atmosphere is, it does help). Hitting an asteroid and returning is roughly twice as hard as hitting Mars and returning because you have to halt your motion at the asteroid using propulsion.

          No, you are thinking linearly. Remember that asteroids have higher orbital energy, so they simply put Hayabusa on a constant-thrust spiral intercept trajectory, thanks to its ion engines. Since gravity is negligible, they only needed small delta-v's for station keeping around the asteroid when they got there. Then when they wanted to leave they just had to do the opposite, slowly bleed away the orbital energy.

          You could do the same thing with Mars, but it's far more difficult because the landing craft wil

        • Hmm... It requires energy to slow down the spacecraft. Which in the case of Mars goes up in heat in the bit of atmosphere, and stuff and heat propelled out in the case of manual breaking with trusters.
          What if we, instead of throwing that energy away, could just transform it into something storable.
          Then we could create at least a part of our fuel in-place, wouldn’t have to carry it all the way, and kill two birds with one stone.

          I think it’s worth pursuing that idea. Especially for missions to som

        • Re: (Score:3, Interesting)

          by blair1q ( 305137 )

          The report is due six months or so

          Oh, horseshit.

          I hate when an experiment is performed and nobody says a word on what happened, even from a qualitative view.

          They can at least describe what it looks like. "Grey dirt" would be plenty to hold me for the 6 months it takes to produce a full assay.

      • Re: (Score:3, Interesting)

        by denmarkw00t ( 892627 )

        You could, in theory, work around these issues in different ways. You could include fuel containers in the payload with parachutes - if we can give the robot some way to find them it can navigate to and attach them when ready. You could also send multiple rockets, some with fuel and one for the robot, but having them find eachother would be more challenging and landing areas would be much more prone to error in the proximity.

        Still, it isn't impossible.

      • Re: (Score:1, Troll)

        by CrashandDie ( 1114135 )
        Duh dude.

        You just said Mars' gravity was only one third of Earth's, so considering it already left Earth's atmosphere, why would the probe have a problem with a one-third-puss-gravity well?

        Seriously, bro, THINK!
      • Moon has gravity that is around a sixth of Earth, and the Eagle module managed to lift off with its more than 10K pounds and 2 men on board. Would it be that hard to bring back a couple kg. of rocks down here?
      • Problems are incentives for creative engineers find a solution.

      • But Mars has gravity that is around a third that of Earth. That's a lot. So a sampling robot would need to land on Mars and then return fighting against the large Martian gravity well. It would probably need to carry its fuel with it which means it would need to have a lot of mass to start with and which would make a safe landing even more difficult. We'll probably have successful sample-return from Mars before a human mission their but the technical difficulty with even a sample-return mission is immense.

        It's not really that much. Delta-V from the surface of Mars to Earth return trajectory is ~8km/sec, which is about double the delta-V from the lunar surface to Earth orbit. Consider the size of the Apollo lander - and that had people in it!

      • It does not have to land with the fuel mass. It only has to land with enough mass to get back to orbit. There it can dock to the fuel that brings it back to earth. Like with the mars landings. If you optimize to the sweet spot, you can save a lot.

      • Re: (Score:2)

        by cyn1c77 ( 928549 )

        ... but the technical difficulty with even a sample-return mission is immense.

        Don't make more of it than it is. The energy budget is immense, but it is well within our technological capabilities. Congress is just choosing to spend money elsewhere.

      • fighting against the large Martian gravity well.

        Your use of "Well" is redundant here. It's obvious that no one should fight Martians badly.

      • Re: (Score:2)

        by jafac ( 1449 )

        Another very difficult (but very seldom talked-about) problem of spaceflight, is re-ignition of rocket engines. At-altitude, in space, on another heavenly body. . . one has to count on the propellant being in good condition (not frozen, not aerosolized, not leaked out through a ruptured tank, line, seal or stuck-valve, not gravitationally globbed in the center of the tank). It's not a trivial problem - and launch of a sample-return vehicle from Mars faces a pretty big challenge that we have not yet addres

  • We'll Never Know (Score:5, Insightful)

    by WrongSizeGlass ( 838941 ) on Monday June 14, 2010 @10:52PM (#32574576)

    The National Geographic coverage of the news gives some air time to those doubtful that this study will prove definitive.

    3.5 billion years ago is too long ago for us to ever *know* definitively. We won't get to Mars for decades and it would be decades after that before any real "hands on" research could even bring us closer to a "definitive" answer (which will still inly be a best guess).

    • Re: (Score:3, Insightful)

      by MichaelSmith ( 789609 )

      The National Geographic coverage of the news gives some air time to those doubtful that this study will prove definitive.

      3.5 billion years ago is too long ago for us to ever *know* definitively. We won't get to Mars for decades and it would be decades after that before any real "hands on" research could even bring us closer to a "definitive" answer (which will still inly be a best guess).

      Are you a geologist?

      • Re: (Score:1, Funny)

        by Anonymous Coward

        No, but I play one on television.

    • Re: (Score:3, Funny)

      by TheKidWho ( 705796 )

      It's going to take us decades to figure out what happened billions of years ago? I don't know about you, but that sounds pretty quick to me.

    • Nah, we could date it really easily. There's radioactive carbon dating. Oh, won't work. Well, you can look at the sedimentation layers. Oh, won't work. Well, there's always guesswork. :)

      Really, the dating itself isn't as important as if water was or was not there.

      I'm still biased towards the idea that there was and still is water there. Well, as NASA said [rense.com], "The way the surface has responded is bizarre. I don't understand it. I don't know anybody on my team who understa

      • Re: (Score:3, Insightful)

        by camperdave ( 969942 )
        There's radioactive carbon dating. Oh, won't work. Well, you can look at the sedimentation layers. Oh, won't work. Well, there's always guesswork.

        Carbon dating and sedimentation layer examination are both guesswork. Educated guesswork, possibly even accurate guesswork, but guesswork nonetheless.

        •     It's fairly educated guesswork though.

              On Earth, we can compare it to known (or estimated) things. The reason I said it wouldn't work on Mars would be, we know nothing about it's history. If (big if) we did find something resembling life, we wouldn't have any way to establish when it happened. Well, we may be able to eventually, but it will be building a timeline from scratch, rather than having centuries of data to work with.

          • We know something about the cratering history -- for instance if one crater is partly on top of another, we know it formed later, and the extent of "weathering" may give us further information. We can also compare it with the much studied cratering history of the Moon.

      • Re: (Score:2, Informative)

        by polymeris ( 902231 )

        Nah, we could date it really easily. There's radioactive carbon dating. Oh, won't work. Well, you can look at the sedimentation layers. Oh, won't work. Well, there's always guesswork. :)

        There are other radiometric dating methods besids carbon-14, specially for things that old. One of them is rubidium-strontium (50 billion yeras half life?). It works on inorganic stuff too, although i don't know if it works for martian inorganic stuff, but I'm sure one could adapt it.

        Really, the dating itself isn't as important as if water was or was not there.

        I agree.

      • Re: (Score:2)

        by vlm ( 69642 )

        There's radioactive carbon dating. Oh, won't work.

        I'm curious why you say that. RC dating works because theres a certain believed fixed ratio of carbon isotopes in the air and general environment, and once something dies and is buried the active isotopes start decaying into the stable isotopes. The active isotopes come from cosmic rays and are very optimistically believed to be constant and/or have been correlated on earth with sedimentation and other data.

        Works just fine with inorganic samples. Crush the heck out of some martian rocks and the trapped a

    • Let us claim our place among the fossils with pride, that we did not stoop to such foolishness before the inevitable asteroid took us.

    • 3.5 billion years ago is too long ago for us to ever *know* definitively. We won't get to Mars for decades and it would be decades after that before any real "hands on" research could even bring us closer to a "definitive" answer (which will still inly be a best guess).

      Actually, I *know* because I was there. I'm just over 4 billion years old. Mars was one-third water. We didn't realize that it wasn't enough to support life, as we consumed most of it watering our Martian golf courses. (Which happen to be much larger than earth courses.)

      Once we lost most of the potable water to golf, we started harvesting the oceans. It never seemed a problem, as water was viewed as an "unlimited" and "cheap" resource.

      Well, it turns out if you kill the ocean you kill the planet. O

      • Re: (Score:2)

        by dwye ( 1127395 )
        H. Beam Piper (or his estate, rather) is going to want his money for poaching his idea. Refuse to pay, and you will end up like Benjamin Bathurst or Calvin Morrison.

        BTW, water used on golf courses automatically recycles (unless you crack the water and use the hydrogen for fusion). Piper's Martian colonists used up Mars in more realistic ways.

    • We won't get to Mars for decades

      Huh? We've been to Mars several times in the past decade already - we are still there if being in orbit counts as being 'there'.

  • Always curious about where the water went (Score:4, Informative)

    by Low Ranked Craig ( 1327799 ) on Monday June 14, 2010 @10:58PM (#32574602)
    So I finally looked it up. Interesting. http://phoenix.lpl.arizona.edu/mars151.php [arizona.edu]

    • Re:Always curious about where the water went (Score:4, Funny)

      by Anonymous Coward on Monday June 14, 2010 @11:28PM (#32574728)
      It is all underground, frozen and waiting for someone to turn the melting reactor on.

      •     It'll be easier to turn it on, with all the mutants with multiple arms (and breasts). And as an added bonus, there'll be some amazingly talented 4 handed piano players.

    • Re: (Score:2)

      by RDW ( 41497 )

      Looks like the Martians must have engineered this quite recently:

      "Its air is much more attenuated than ours, its oceans have shrunk until they cover but a third of its surface, and as its slow seasons change huge snowcaps gather and melt about either pole and periodically inundate its temperate zones. That last stage of exhaustion, which to us is still incredibly remote, has become a present-day problem for the inhabitants of Mars."

      - HG Wells, _The War of the Worlds_ [1898]

  • We can be like them in 100 years, assuming we get some nuclear bombs going.
    • We'd need tons upon tons of nuclear weapons to practically do that though. Earth has an atmosphere where mars does not, evaporating water doesn't go into nothingness but rather back into the atmosphere. Sure if you nuclear-ly fuse H2O into heavier elements it could work, but its way more bombs than would ever be practical to use.

      •     You never know until you try. Either way, we'll be able to bask in the glow of our new radioactive neighbor for generations. :)

      • Re:Not funny (Score:5, Informative)

        by Zocalo ( 252965 ) on Tuesday June 15, 2010 @12:03AM (#32574844) Homepage

        Earth has an atmosphere where mars does not

        Mars has an atmosphere, not much of one to be sure, but it does have one. Why else do you think so many landers used parachutes to help slow their descent?

        • Re: (Score:3, Funny)

          by Rakshasa Taisab ( 244699 )
          Those were lovechutes; the good energies radiating from Mother Mars slowed the descent.

        • Mars has an atmosphere, not much of one to be sure, but it does have one. Why else do you think so many landers used parachutes to help slow their descent?

          Huh. I always thought it was for nasa to get a little extra funding on the side. That way as the native Martians watch the probe descend, they can see a big 'chute (with a big ad on it) pop out too. How else will they know how good Pawtucket Patriot Ale really is?

  • Intelligent life (Score:3, Funny)

    by owlstead ( 636356 ) on Tuesday June 15, 2010 @12:03AM (#32574840)

    OK, the ocean has been established. Maybe we can go and look for oil pollution to see if there was intelligent life on mars already?

  • Once upon a time... (Score:4, Interesting)

    by Anonymous Coward on Tuesday June 15, 2010 @12:10AM (#32574868)

    Philip K. Dick wrote several short stories about how we lived on Mars and didn't remember to reduce, reuse, recycle, curb our species appetites for violence (war) and sex (overpopulation). So we burned up the oceans when it all went kaboom!. But not before we sent people to live on Earth...

    Now there are "billions and billions" of us. (sigh)

    • Re: (Score:2)

      by vlm ( 69642 )

      curb our species appetites for .... sex (overpopulation)

      We've got great technological solutions for that particular problem, its just the religious lunatics don't like it. Need to go to the root cause, not just list a symptom, which in that case would be religious lunacy. And pretty much all major world religions, except Buddhism, glorify warfare and demonize the victims, so the loons get some blame there too. And pretty much all major world religions glorify the opposite of "reduce", obviously thats how they got to be major world religions instead of some an

    • See also Ray Bradbury's The Martian Chronicles [wikipedia.org].

    • Re: (Score:2)

      by khallow ( 566160 )
      Since my previous reply was modded down for some reason, maybe my explanation needs to be clearer for the moderators. Phillip K Dick is fiction. Sure there is some tenuous basis in reality, but ultimately it makes no sense to get depressed simply because you read a few very speculative (and wrong, I might add) stories about an imaginary human past. Remember that Dick could bend reality to enforce whatever point of morality he chose to make. He is shoehorning his world and characters into whatever belief sys

    • Re: (Score:2)

      by dwye ( 1127395 )
      Are you certain that you did not mean H. Beam Piper? Most of his stories are set in a Multiverse built around different probability worlds keeping or losing Martian technology to different extents, then diverging. One time line kept all of the Martian tech, then developed the ability to cross to other lines before completely ruining their Earth, which is how the stories mesh together.

    • Yeah, billions and billions of hairdressers, tired TV producers, insurance salesmen, personnel officers, security guards, public relations executives, management consultants...

      Apologies to Douglas Adams.

    • Re: (Score:2)

      by blair1q ( 305137 )

      The part about a spacefaring society completely forgetting that it has the ability to make anything more complicated than stone axes is the part that i can't suspend disbelief of.

  • Related TED talk (Score:2, Interesting)

    by Anonymous Coward

    One of the recent TED talks about returning to Mars mentioned this.

    In http://www.ted.com/talks/lang/eng/joel_levine.html (16 minute video) Joel Levine describes how

    * We've found plumes of methane in the Mars atmosphere above some of the coastal and structures mentioned in this article
    * On Earth, over 99.9% of methane is produced by living systems
    * Our next mars mission should not be a lander, but a robotic aerial flyer that can give more precise measurements of methane and other gasses along with improved g

    • Well the Mars Science Lab (another rover) has been in the works for a while, so that's still a go. Then, sticking to the lander-orbiter-lander-orbiter schedule, the MAVEN orbiter is next. Both are equipped to provide some detail on the methane, but now NASA actually wants to send a dedicated orbiter [wikipedia.org] for that.

      Also of interest, there are several mission proposals summarized here [wikipedia.org]. Two of them are UAV missions, including KittyHawk (a proposal that has lost several times, first proposed for a mission in 2003

  • Where mighty Throxeus once rolled, now there is only the ochre moss of the dead sea bottom. Oh bugger my flyer's crashing AGAIN, I really am going to speak to the maintenance guys when I eventually fight my way back to Helium

    • Re: (Score:2)

      by AGMW ( 594303 )

      Where mighty Throxeus once rolled, now there is only the ochre moss of the dead sea bottom. Oh bugger my flyer's crashing AGAIN, I really am going to speak to the maintenance guys when I eventually fight my way back to Helium

      Is it only me that read that in an oddly high pitched voice?

  • and they've found evidence of a deep water drilling that seems to have occurred about the time when the water started decreasing......

  • ...that Mars was covered by a chocolate ocean with marshmallow fish in it.Where do I collect money for my research?

    • Re: (Score:1)

      by maxume ( 22995 )

      Why do you think that coming up with the wacky idea is the valuable part? The valuable part is writing a reasonable sounding grant proposal based on the wacky idea.

  • Maybe the earth and mars were one planet(AKA "Pangea") about 3.5 billion years ago when a giant asteroid(AKA the moon) hit "Pangea" and knocked the mars part back. Thus our continents started shifting again, and the dinosaurs could no longer survive with a smaller planet. It would then make sense that America accidentally gave New Zeland a chunk of fossilized wood brought back from the moon. It could also explain our planet's weird rotation and why the moon doesn't rotate while it orbits us.

  • If there was that much water on Mars, and now it's not, then it likely went out into space with the solar wind. Which means some of it will have fallen to Earth.

  • We have known that Mars used to have water since the Viking probe in the '70s, [uncoveror.com] and that the martians had to go underground. Why are they pretending this is not old news?

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