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Mars NASA Space Science

Mars Images Reveal Evidence of Ancient Lakes 128

Matt_dk writes "Spectacular satellite images suggest that Mars was warm enough to sustain lakes three billion years ago, a period that was previously thought to be too cold and arid to sustain water on the surface, according to research published today in the journal Geology. Earlier research had suggested that Mars had a warm and wet early history but that between 4 billion and 3.8 billion years ago, before the Hesperian Epoch, the planet lost most of its atmosphere and became cold and dry. In the new study, the researchers analysed detailed images from NASA’s Mars Reconnaissance Orbiter, which is currently circling the red planet, and concluded that there were later episodes where Mars experienced warm and wet periods."
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Mars Images Reveal Evidence of Ancient Lakes

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  • Until we go there and see. Interesting idea though.
    • by carlhaagen ( 1021273 ) on Tuesday January 05, 2010 @11:50AM (#30655558)
      The images speak pretty clearly for themselves, and have done so for a long time. We already know since forever what formations liquid deposits create over time on malleable surfaces.
    • What is so special about humans manipulating measuring equipment versus robots? This notion that we must send people into space is just romantic.

      • What is so special about humans manipulating measuring equipment versus robots? This notion that we must send people into space is just romantic.

        The romanticism of the adventure is one of the strongest motivators of exploration. Take that away, and it's just work.

        Besides, there are practical reasons for sending humans into space. One day, in order for the human species to survive, we will have to move off this rock and travel to other regions of our galaxy. We might as well start our baby steps now.

      • Re: (Score:3, Insightful)

        by khallow ( 566160 )

        What is so special about humans manipulating measuring equipment versus robots?

        We do it better.

      • Re: (Score:1, Insightful)

        by Anonymous Coward

        Because people can wander around navigating the terrain a lot better and quicker. Now imagine the person is in fact a geologist. They can immediate analyze what they are seeing, move around looking for interesting things, all the time E.g. "Ooh, that's an interesting rock". WHACK. "Hmm, look at that...". Now compare that to an incredibly slow robot that has to inch around, take a picture, send data home, have it processed here, wait, wait, wait. Experts here decide to move the robot 2 feet to the left. wait

        • Re:Why? (Score:4, Informative)

          by natehoy ( 1608657 ) on Tuesday January 05, 2010 @04:07PM (#30659652) Journal

          The limitations of our current robots were based on space, cost, and durability. A geologist might be able to search the terrain faster, but they won't be able to be there for more than a few days or weeks at best, and each geologist could really only search one general area. In the same space as your single geologist and all the food and resources he/she will need, we could explore multiple places on the surface of Mars with a generous handful of Spirit-type robots, and they could all stay there for years collecting data.

          The reason Spirit and Opportunity are so slow is because they operate on a small solar array, that generates (at peak) 140 watts for the 4 hours of daylight they get in a Martian day. That's about 560 watt/hours an m-day at best, and that's all the energy they need to do what they do. That's a lot of science packed into that amount of energy. They are currently getting a fraction of that due to dust on the arrays, and yet they are still collecting good science, six years in.

          If you want enough energy to support a human being there, you're talking nuclear engines. If you're going to make that kind of energy available, you might as well power the robots with nukes - they will then be able to move faster than a human could, and there could be hordes of them for the same cost and resources expended sending one human. And they could stay for years.

          To get a single human to mars, on the surface, and back to Earth, you'll need about a half ton of dehydrated food, enough water to recycle so they have a continuous supply, and probably a few thousand watt-hours a day minimum for the entire trip for heat, light, etc. You'll also need radiation shielding (likely tons of it) for the multi-year trip, room for them to exercise, many tons of fuel for the two-way trip, etc.

          Spirit weighs about 400 pounds, or a little over twice the weight of a human. But you save the half-ton of food, the water, more than half the fuel (no return trip, no need to re-orbit it), and almost all the energy needed to sustain life during the voyage. The ship is simpler, since you need almost no shielding, no living space - just strap a few (or a few hundred) robots around the outside of a rocket engine.

          Take a science team of a dozen, and you could probably have at least 50, maybe 100 robots take their place. And those robots would be able to work there for years. Each could have its own nuclear plant and probably have power and functioning instruments for decades (energy starvation from the solar cells is what is slowly killing off the current robots).

          Plus, robots can make a one-way trip. No need to store fuel to bring them all back, just enough for a few dozen of them to send a sample back to a central ship in orbit, which can then pack up the samples and send them back on a relatively small rocket that weighs a few hundred pounds.

          • by khallow ( 566160 )

            Take a science team of a dozen, and you could probably have at least 50, maybe 100 robots take their place.

            No, you couldn't. My view on this is simple. A human presence on site is superior to sample returns which in turn are much superior to probes controlled remotely from Earth. We only need to look at how we do science on Earth to see that. Most of it is done directly by humans. In a sufficiently large project where the overhead of using humans (and the cost of putting mass on Mars) is reduced greatly by economies of scale, I see humans occupying the same research and exploration roles they take on Earth.


        • Now compare that to an incredibly slow robot that has to inch around, take a picture, send data home, have it processed here, wait, wait, wait.

          Yeah, but if you sent a human with enough food and resources for a 3 month mission, what do you reckon the chances are that they will still be around doing the same thing six years later?

          Robots might indeed be slower, but on a cost and support basis, they utterly hands down smash any human in a support scenario. Also, the rovers touched down in a module around the size of a small car from memory. Also the support habitat didn't need to move with the robot.

          Lastly, why do you think really makes somethin

    • 3.8 billion years is a long ways for humans to time travel and see. guess we'll just have to continue to make educated guesses off the data provided by the rovers and current orbital observers.

  • by tetrahedrassface ( 675645 ) on Tuesday January 05, 2010 @12:14PM (#30655934) Journal
    Europa may well be warm and wet under the layer of ice. In fact Europa probably is, and might in fact harbor life. Can we please forget about Mars? Mars sucks because we keep going there and not really finding anything of importance. I am tired of Mars, there are other, more interesting places to explore.
    • Re: (Score:1, Redundant)

      by neo-mkrey ( 948389 )
      All these worlds are yours, except Europa, attempt no landing there...
    • by elrous0 ( 869638 ) *
      Even if Europa does contain such life (and that is still a VERY big "if"), the effort to pinpoint it and drill down to it would be a helluva lot more trouble than sending any little probe to Mars. That's *way* beyond NASA's budget or ambitions. Admittedly, it would be no more or less pointless than any of their other money-sinks, but don't hold your breath.
    • by sznupi ( 719324 )

      And we can't explore both...why exactly? (plus mission to Europa is being worked on; though it will be not an easy feat)

      As a matter of fact, why do you want to limit us to Europa? Why do you dismiss Mars outright? (there are still those weird methane emissions we have to sort out; and possibility of subsurface water) Also, what makes you think Europa is more likely to harbor life than Ganymede, Callisto, high atmosphere of Venus or even Enceladus?

      Mars has one big advantage of being relatively easy to get th

      • I didn't say anything about limiting us to Europa, you did. It would be a very good thing to explore not only Europa but the other moons you list. The reason we keep going back to Mars isn't so much for the science because there is a hell of a lot of other and possibly more interesting science that could be better served by going to Europa, or maybe Enceladus. The reason I dismiss Mars outright, on its face, and with no reservations is that given our budget it would be better to let Mars rest for a time,

        • Re: (Score:3, Informative)

          by Grishnakh ( 216268 )

          We could learn a lot from Europa because Europa has a small iron core which is heated by tidal friction, and under the the 3km of ice there may in fact be 100-200 kilometers of salt water . Now it is odd, that our space agencies, that claim to be searching for life willfully have ignored Europa other than a few flybys.

          Maybe they're put off by that 3km of ice. How exactly are they going to drill through that ice, when the best we've managed so far with remote probes is to launch a few wheeled rovers to a dr

          • by geekoid ( 135745 )

            It's hard, but if we put an effort and money into it, I have no doubt would could solve those problems. Solutions have been proposed.

            Studying Europa isn't impossible, nor is it harder then Mars, just different.
            We can, and should study Europa, it has a strong likelihood of life, right now, not the possible of life millions of years ago.

            • Again, "walk before run" applies here. We're having a lot of trouble just getting some simple wheeled rovers to operate reliably on a DRY planet that's only 30 light-minutes away. Don't you think we should figure out how to make our autonomous space hardware work a little better before we attempt to take on a mission involving a moon many light-hours away, which involves drilling through 3km of ice (a serious feat here on Earth), and then exploring what's most likely an under-ice ocean?

              And second is the m

          • Ahh, we can melt through that with a small self contained probe that is RTG powered. It could be designed it to melt its way in, and climb down the hole as it goes. I don't see that as hard.. It could then release a probe or a number of gliders to roam about. The gliders could even be powered by their own small RTG's which would allow them to be driven!

            As far as communications fhrough the ice well there is research in this area like this that utilize high loss. Take this article for instance: "Underwater c []

            • That's a good idea about melting through the ice, though I do wonder if an RTG would generate enough heat to do that. But the rest of the things you're talking about are still fairly new here on Earth, let alone on another planet. Wheeled rovers are comparatively simple, and we're still having trouble with them on Mars with some simple dirt.

              I imagine the reasons they're focusing on Mars are 1) it's very close, much closer than Europa; 2) it's all dry land. It's much easier to operate stuff on dry land, f

            • Another interesting point: NASA and ESA (with JAXA and Roscosmos expressing interesting in joining in) are planning a mission to the Jupiter moons, with a focus on Europa, Ganymede, and Jupiter's magnetosphere: []

              So they're not completely ignoring Europa.

        • by vlm ( 69642 )

          Mars is just too easy

          Your rant was actually doing pretty good until there. Check the mars mission failure rate... If Europa were say, a hundred times more difficult, then the odds of total mysterious failure in Europa currently approach 100%. But if we can improve our reliability by trying stuff in easier mars missions, maybe someday a Europa mission wouldn't be a guaranteed failure, and might even work, maybe.

        • I didn't say anything about limiting us to Europa, you did.

          Uh, you said "forget Mars", so it seems pretty clear that whatever unlimited space program you're imagining, it is limited to not-Mars.

          In short Mars has received a disproportionate number of missions yet we keep sending rovers and landers to Mars!

          Because we still have a ton of things to learn and it's low-hanging fruit. Relatively cheap missions with a relatively high measure of success and an enormous payoff in science. We will be sending rovers

    • No, we can't forget about mars, because we still have a crap-ton of stuff left to learn about it. So much so that just about everything we do there results in us learning something new. Hell, just a day or two ago, I learned that the Spirit rover trying to work its way free from some sand had revealed sulfate deposits. And that was quite literally just scratching the surface.

      As others have pointed out, Europa missions are in the works, but are quite a bit harder to do than Mars, especially if you think t

  • So would 'global warming' have prevented this type of disaster?

    • So would 'global warming' have prevented this type of disaster?

      Uh, no. Or do you really believe global warming would've magically allowed Mars to hold on to its atmosphere?

    • No. The problem with mars is that it lacks the gravity to keep gaseous particles bound to it's atmosphere, such that the solar wind removes a really small % of it's atmosphere annually.

      • Re: (Score:3, Insightful)

        So if you were generating the same % of gas annually, would it not be in equilibrium?

        • Correct, which is why we can still breathe :) Realize that most of a planet's mass is not involved in the generation of the atmosphere, and that aside from Volcanos not much change occurs on a 1000 year scale unless biological processes are involved. Volcanic activity has also substantially reduced on Mars, which would have been the other major factor in producing atmospheric gases from minerals / rocks.

          The off-set of having a warmer atmosphere though is that warm things expand, which makes them easier

          • by al3 ( 1285708 )
            Does the earth's magnetic field not also provide our atmosphere a degree of protection from solar wind that Mars does not benefit from?
            • From Charged particles, yes. Not all space particles are charged, or are slowed down by magnetic fields.

              Mars is lacking a magnetic field, which is also believed to be why volcanism has stopped. (molten core not large enough, or maybe fully solid )

  • But what have you done for us LATELY?
  • the photo shows liquid exchange between craters. Couldn't this be something apart from water?
  • So, the aliens have successfully stolen all of the water from Mars (as reported in thousands of lousy science fiction movies and TV dramas). Is the Earth next on their list of planets to steal the water from? I mean, it's not like you could possibly manufacture your own water by taking a couple of common elements in the universe, like hydrogen and oxygen, and combine them using a stupid trick like fire.

  • Our ancestors were the original inhabitants of the Red Planet who seeded life here after determining their home world was doomed to destruction (massive asteroid impact is my guess).

    Sorry, too much Clarke and Heinlein as a kid I suppose.
  • "Channel connecting depressions in bottom right providing clear evidence of liquid exchange between depressions."

    Around here, we call that a "river"... XD Most lakes have one or two connecting them to other bodies of water.

  • we're safe from terror...

Today is the first day of the rest of your lossage.