back to article No, we haven't found liquid water on Mars, says NASA

The idea that seasonal dark streaks on Mars indicate the presence of liquid water turns out to be a dry argument. NASA last year advanced a theory that dark gullies called recurring slope lineae (RSL) that appear during the Martian summer were evidence of liquid water on Mars, albeit liquid water bonded to mix of salty …

  1. Pascal Monett Silver badge

    Grasping at water straws

    Looks like we're going to have to face it : Mars only has some water at the poles - and not enough to sustain a planet-full of colonists.

    That, along with the eternal issue of the thin, non-breathable atmosphere, is going to make a colony on Mars a very difficult endeavor.

    1. wolfetone Silver badge

      Re: Grasping at water straws

      "That, along with the eternal issue of the thin, non-breathable atmosphere, is going to make a colony on Mars a very difficult endeavor."

      Well, of course it will with that attitude.

      1. Tom Paine

        Re: Grasping at water straws

        Yes, because the attitude that science can tell us anything about the difficulty of mounting a manned mission to Mars' surface is just Project Fear. Right kids?

        1. Anonymous Coward
          Anonymous Coward

          Re: Grasping at water straws

          Given people can live in space for prolonged periods then Mars or the Moon should both be doable. Just very difficult, and that's the point really."Not because they are easy, but because they are hard" https://www.youtube.com/watch?v=kwFvJog2dMw

    2. Anonymous Coward
      Anonymous Coward

      Re: Grasping at water straws

      The lack of water is not as big a problem as the lack of a Martian magnetosphere, without which hard solar radiation can reach the surface; any colony on Mars would need to live either beneath the surface or inside shielded structures (that same lack of a magnetosphere also means that any project to terraform Mars, to add a breathable atmosphere, would have to be on-going and not a one-time effort).

      To establish a colony on Mars we'd first have to send the shielded structures for people to survive in while they assemble the machinery needed to excavate the sub-surface habitats - that's a lot of very heavy stuff that has to be got from Earth to Mars.

      Which is not to say that it's not doable, just that it will be very difficult, will take a long time, cost a lot of money and most probably a few lives.

      1. Anonymous Coward
        Anonymous Coward

        Re: Grasping at water straws

        subsurface it probably the best bet, or cave networks if they exist. As it isn't only radiation but also meteors that you want to hide from. You would have some surface things, power and hydroponics most likely... anyway it's difficult, complicated but interesting and will take a monumental effort and probably hundreds of years and likely after the moon and after space based mining is a reality. Mining for the sake of greater independence in space not to send things to Earth which has plenty of easy to get mineral resources as it is.

        There will also be a long way between being able to have people live on extraterrestrial bodies with support from Earth and being able to live there independently, which of course is the goal as it will exponentially increase humanities chances of surviving extinction events.

      2. Anonymous Coward
        Stop

        Re: Grasping at water straws

        > [ ... ] the lack of a Martian magnetosphere, without which hard solar radiation can reach the surface; any colony on Mars would need to live either beneath the surface or inside shielded structures

        That, plus the difference in gravity - Mars' gravity at surface being 38% of that of Earth at surface.

        Life originating on Earth assumes Earth's gravity - simply because it has evolved for 4 Billion years in Earth's environment, with Earth's gravity.

        Place this life form in some other environment, with sharply different gravity, and bad thing start happening to it.

        This is what Mars One says happens to Life from Earth transplanted to Mars.

        And this is what NASA says will happen to Life from Earth transplanted to Mars. Amongst other really bad things (irreversible osteoporosis, high blood-pressure, kidney damage), the heart will atrophy and then stop beating. All because of the change in gravity.

        Not discussed here at all: effects of radiation received during transport to, and stay on, Mars.

        Good luck with these dreams of relocating to Mars.

        1. Anonymous Coward
          Anonymous Coward

          Re: Grasping at water straws

          I'd be very cautious indeed about any info gleaned from Mars One. It;s also worth pointing out that as no life from Earth has yet been transplanted to Mars what's being talked about is someones best (and hopefully, well-informed) guess sa to what is likely to happen. personally, I'd love to see a robotic lander carry a small automated 'greenhouse' to Mars, so that actual data could be gathered regarding teh effect of 0.38G on plants, prior to our sending a manned mission there. However, I suspect it's more likely that what will actually happen is a manned mission dependent on freeze-dried foods will take some plants with them to attempt the experiment once there.

          As for osteoporosis - absolutely a potential problem for anyone going to Mars and then coming back. Similarly, possible effects on blood pressure, and this is at least partly why some folk (eg Buzz Aldrin) suggest instead asking for volunteers to colonise Mars (ie: go and stay) right from the start, rather than at some indefinite time in the future. Aside from that making the missions involved smaller, lighter, cheaper and safer (because more of the mission tonnage can be put into keeping the colonists alive and well than with a return mission) has some obvious attractions. Where that notion tends to hit problems is in the ethical issues that arise - some folk just don't like the idea of anybody being sent on a one-way mission to Mars, never mind if it's volunteers only. (I'd add that realistically, there would be the possibility of bringing some folk back from Mars eventually. However, ethical questions arise if the living conditions just are not really suitable for whatever reason, and if the volunteers cannot be bought back in time. Then we're into 'suicide pill' territory, with all the ethical brouhahah THAT entails).

          From the point of view of producing materials once on Mars, I commend Zubrin's 'The Case for Mars' to anyone interested. Whilst I do think Zubrin may have underestimated the physical and psychological side of things, I doubt that his numbers on the physics and chemistry are very far out. I don't think there's much doubt that we can set up otherwise livable bases on Mars, if we wish to. The question is whether the medical side of things will cause any insurmountable problems, and what we make of the ethical questions raised.

          One things for sure though - it'd be a lot easier to get good answers to some of the big questions about Mars with human boots on the ground.

        2. tony72

          Re: Grasping at water straws

          @ST - your links are both talking about what happens to people in zero gravity, not in Martian gravity; in other words, effects suffered during the journey to Mars, rather than after they arrive. They both talk about potential methods to counter those issues, so they're hardly insurmountable. That's not to say that Martian gravity won't cause some issues, but 38% of Earth's gravity is a very different case from zero gravity.

          1. Anonymous Coward
            WTF?

            Re: Grasping at water straws

            > your links are both talking about what happens to people in zero gravity, not in Martian gravity

            No, these links talk about what would happen on Mars, while experiencing Martian gravity.

            MarsOne is about humans traveling to, and living on, Mars. They don't expect zero gravity on Mars, do they?

            The NASA link is also explicitly about Mars, Martian gravity and its effects on the human body.

            Apparently, you cannot read and understand simple English. That makes you an authoritative reference on Martian gravity and its effects on the human body.

            1. tony72

              Re: Grasping at water straws

              I'm afraid it's you that can't read. Going to Mars involves a trip through space, and that is what the links refer to. Let me give a few quotes from your NASA link;

              Strange things can happen to the human body when people venture into space -- and the familiar pull of gravity vanishes.

              That's the sub-heading. Note "venture into space", "gravity vanishes".

              In zero-G, muscles atrophy quickly, because the body perceives it does not need them.

              Paragraph 2. Note "zero-G", not martian G.

              Within two to three days of weightlessness, astronauts can lose as much as 22 percent of their blood volume as a result of that errant message.

              Paragraph 4. Note "weightlessness".

              The question is, do such losses matter? Perhaps not if you plan to stay in space forever.

              Oh look, we're still talking about space, not Mars.

              "You want the crew members to function normally when they come back to Earth ... and not have to lie around for long periods of rehabilitation," he says.

              And Earth isn't the only planet that astronauts might visit. One day humans will journey to Mars -- a six-month trip in zero-G before they disembark on a planet with 38% of Earth's gravity. "[We'll have to maintain] those astronauts at a fairly high level of fitness,"

              Paragraph 10 or so. Now here we do mention Mars, but notice the context; we're talking about Mars as another gravitied destination for the astronauts, like Earth. The article is talking about maintaining the health of the astronauts while they are in space, so that when they land on a planet, be it Earth or Mars, they are able to function.

              The article is absolutely clear that it's talking about health issues resulting from weightlessness while the astronaughts are in space, not effects experienced under Martian gravity, and it's a complete mystery to me how anyone could read it otherwise.

        3. Anonymous Coward
          Anonymous Coward

          Re: Grasping at water straws

          Given the amount of heavy stuff that would need to be transported to Mars, just to start colonisation, I think we'd have to be looking at pretty big spacecraft, being assembled in either Earth or Luna orbit, and which would make a centrifuge plausible for the crew quarters.

          1. Anonymous Coward
            Anonymous Coward

            What's the point of a colony on Mars?

            It would take massive investment for many generations before it could become truly self sustaining - i.e. able to continue to progress forward technologically completely separate from Earth (if we took a massive impact and civilization here - if not all human life - was ended)

            Aside from the "backup of humanity in case Earth is destroyed", why have a permanent colony on Mars? Why is it better to live there than the Moon? The Moon is less hospitable, but Mars is so inhospitable that the difference is academic, and due to shorter distance and lower gravity it would be far quicker and easier to bootstrap a lunar colony than a Martian colony. Sure, there is a possibility that Mars could someday be terraformed, but until we really know how to do it that's no more realistic than planning to build a ringworld.

            1. Anonymous Coward
              Angel

              Re: What's the point of a colony on Mars?

              > [ ... ] why have a permanent colony on Mars? Why is it better to live there than the Moon?

              None of these futuristic scenarios have any chance of becoming reality in the foreseeable future. These are nothing more than social media discussion fodder.

              Plus, talking about Life on Mars - Real Soon Now - is very convenient for our rulers: they don't have to talk about the giant problems we are facing here and now. Look, there's a new planet, right around the corner! All we have to do is get there!

              It only takes a small percentage of gullibles who can't or won't understand physics to completely drown in irrational noise any hope of a rational discussion about mankind's probability of ever colonizing another planet - yes, this probability is very close to zero.

              See the other discussion about the newly found Goldilocks planet orbiting Proxima Centauri, and how we're going to travel there Really Soon Now, beause it's only 4.2 light-years away from us, and it has life. Not.

      3. Captain DaFt

        Re: Grasping at water straws

        "To establish a colony on Mars we'd first have to send the shielded structures for people to survive in while they assemble the machinery needed to excavate the sub-surface habitats - that's a lot of very heavy stuff that has to be got from Earth to Mars."

        Or we could land at existing caves, and set up temporary shelters inside them whilst we build the permanent ones.

        Take Olympus Mons, for example. Huge, HUGE, volcano, riddled with caves and tunnels.

        Find an underground dome about 1-2 km across, preferably near the top for ease of getting on/off the planet (Did I mention that it's HY-UUUGE?), and set up a habitat in there for long term, or use smaller caves for short term outposts for exploration.

        Natural rock shielding from solar/cosmic radiation, plus insulation from cold.

  2. Yesnomaybe

    Oh I don't know...

    "...we'd expect warmer zones to be more conducive to liquids forming and flowing."

    Stands to reason then, that these warmer areas could have dried out quicker, so there is no groundwater left to form streaks? And water in the ground need not be evenly distributed, so an absence of streaks in similar zones is not a deal-breaker for me.

  3. Tom 7

    Things fade in the sun - even on Mars.

    Or get dusty. I'd put money on there being very little water on Mars - a lot of the things claimed to be evidence of water can be explained by wind and dust erosion or the effect of dry lahars.

    One advantage of the dryness is at least solar panels will work pretty well at high latitudes so we can at least colonise the poles.

    Sunday lunch with the neighbours is going to be a long trip mind.

    1. Tom Paine

      Re: Things fade in the sun - even on Mars.

      There's a lot of incontrovertible evidence of water ICE in the shallow sub-surface; apart from tons of spectroscopy from orbit, you may remember that Mars Phoenix actually dug some up a few years ago:

      http://imagecache.jpl.nasa.gov/images/640x350/sol_020_024_change_dodo_v3_516-387-640x350.jpg

    2. Alister

      Re: Things fade in the sun - even on Mars.

      One advantage of the dryness is at least solar panels will work pretty well at high latitudes so we can at least colonise the poles.

      Just so long as you keep the dust off them...

  4. What? Me worry?
    Happy

    I love this

    It's exploration, and trying to figure out the mechanics of why something is the way it is. What was a hypothesis for an observed phenomena is revised and a new explanation is proposed. In a few years or so, it will be revised again. Along the journey we learn more and add to our understanding of our surroundings. :)

  5. Anonymous Coward
    Anonymous Coward

    Surely the best way to find the wet patch on a mass of this size is to roll it in flour?

  6. Tom Paine

    Earlier work

    "NASA last year advanced a theory that dark gullies called recurring slope lineae (RSL) that appear during the Martian summer were evidence of liquid water on Mars, albeit liquid water bonded to mix of salty compounds called “chlorates” and “percholorates”."

    Mike Malin and Ken Edgett of MSS (the company that built most of the cameras at, and on, Mars over hte last 20 years) advanced the theory that the streaks were liquid water outbursts from sub-surface aquifers a bit earlier than that...

    "Evidence for recent groundwater seepage and surface runoff on Mars": M. C. Malin, and K. S. Edgett:

    Science, 288, 2330–2335, doi:10.1126/science.288.5475.2330, 30 June 2000.

    See also e.g. http://www.msss.com/biographies/edgett/edgett_papers.html

  7. Anonymous Coward
    Anonymous Coward

    W. M. D

    Just say you found WMDs on Mars. All the funding!

    1. Anonymous Coward
      Anonymous Coward

      Re: W. M. D

      I think that's oil no?

      1. energystar
        Alien

        Re: W. M. D

        Microbial sh!t draining out?

  8. Novex
    Joke

    Seems to me that the only way to find out...is to go there ourselves. Enough with these namby-pamby robots, send real men, with really powerful power tools, and go dig up Mars! ;-)

    1. Alister

      Seems to me that the only way to find out...is to go there ourselves

      Exactly, all these namby-pamby robots with crappy sensors, just get a bloke to go and stick his finger in a dark patch, he'll soon tell you if it's wet.

      (and if it isn't, he can always have a rest break).

  9. energystar
    Holmes

    Once exposed so transient it don't reach the bottom of the slope. Too much expectation from this test. They would have to be looking at it, at the precise moment.

  10. tempemeaty
    Big Brother

    NASA intentionally discouraging interest?

    I'm calling B.S on NASA. I think they have found water by more than one means and this kind of release makes me wonder if there's an agenda to cause disinterest in manned exploration. NASA is like a kid that doesn't want to go somewhere and so drags his feet all the way...

    1. Yesnomaybe

      Re: NASA intentionally discouraging interest?

      Seriously?

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