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NASA Announces Discovery of Salty Water On Mars ... Maybe

Today's promised mystery announcement from NASA has finally been made: dotancohen writes "A NASA orbiter has found possible evidence for water on the surface of Mars that flows seasonally. The water likely would be salty, in keeping with the salty Martian environment." Adds an anonymous reader: "Dark, finger-like features appear and extend down some Martian slopes during late spring through summer, fade in winter, and return during the next spring, NASA says, and repeated observations have tracked the seasonal changes in these recurring features on several steep slopes in the middle latitudes of Mars' southern hemisphere." You can find more on the claimed find at NASA TV.

6 of 204 comments (clear)

  1. Re:Pictures of the cycle? by Anonymous Coward · · Score: 5, Informative

    How about a video?

    http://www.nasa.gov/multimedia/videogallery/index.html?collection_id=14483&media_id=104892521&module=homepage

  2. Important for two reasons by JoshuaZ · · Score: 5, Interesting

    This is important for two reasons. The first reason this is important is the obvious issue that the presence of liquid water makes the existence of life a lot more likely. It seems that conditions for life are really surprisingly common. What we still don't know is how likely life is to form in the first place and how easily it travels. There is speculation about panspermia and life on Earth having come from Mars on meteorites but the orbital mechanics make that direction a lot more likely than from Earth to the Mars.

    The second reason this is important is that in the long-run colonization and exploration of Mars will be a lot easier if water is easily available. The presence of water will be directly helpful for some plans aside from directly helping humans. For example, the Mars Direct plan http://en.wikipedia.org/wiki/Mars_Direct involves exploratory missions to Mars where some of the rocket fuel for the return is methane made on the surface. Current versions of that plan call for bringing the necessary hydrogen to Mars. This isn't too bad since hydrogen is only a small fraction of methane by mass. But if we could split the water using electrolysis and get the hydrogen directly from that that would potentially further reduce the amount of mass needed to be launched from Earth. Unfortunately, the water here seems to be not so common that one could actually rely on this. This is probably non-viable unless one had much better maps of where the water was, how deep it normally was, the exact locations of the water, detailed knowledge of what salts were making the water briny and any other major chemical contaminants which could make electrolysis machinery unhappy. So overall, this is unlikely to impact missions to Mars in that direct a way.

    1. Re:Important for two reasons by Pharmboy · · Score: 5, Insightful

      Yes, but at some point, you want actual boots on the ground. If the goals of space travel do not include eventually getting humans off this rock, well, then not only is the interest in it going to be near zero, but the point as well.

      Unmanned craft can do some of the best science, including helping us figure out where to land the boots.

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  3. Re:Salty water seeping out of Mars in the summerti by madhatter256 · · Score: 5, Informative

    Something like that.... It could be briny salt water or something else...

    Lisa Pratt used the example of putting a bottle of soda in the freezer to a reporter asking questions.... Before soda completely freezes, the bottle of soda forms an ice made of pure water and it is surrounded by a concentrated solution of sugars and syrup that is super sweet still in liquid form. A similar freezing process is believed to be happening in Mars, where they think it is a briny solution that is seeping out of the surface from the underground ice water as that solution has yet to freeze compared to ice water.

    It's pretty cool stuff. If there are seasonal cycles like this in the subsurface of Mars, then it is most likely that there are some extreme microbes in there that feed off of this solution... They say that if earth had no seasons, then there would be very little diversity in life and this finding shows there are seasonal cycles that might possibly support life.

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  4. Re:civilisation is collapsing- no it isn't by JoshuaZ · · Score: 5, Insightful
    I remember, decades ago, caring about this sort of stuff. Now I realise that it's just another way of appropriating resources to have fun while others suffer.

    Overtime, the amount of suffering has gone down by many metrics. For example, in most of the developing world, infant mortality now is much less than it was 50 years ago. http://en.wikipedia.org/wiki/Infant_mortality The infant mortality rate of the planet as a whole has gone down by a factor of about 3 compared to the rate in the 1950s. The world's level of literacy is also increasing. Average lifespan has also gone up in the developing world. More importantly, that lifespan increase has occurred even if one just looks at the average lifespan of people who survive 3 years of age (this helps deal with most of the infant mortality issue). So no, civilization isn't collapsing. In fact, civilization is doing quite well.

    Sure there are things we can do in the here and now to help people directly, like give more money to help deal with malaria and the like. If you want to really care about your own money going to optimal causes, a good thing to look at is Givewell http://www.givewell.org/ which identifies efficient, underfunded charities that are doing helpful work, especially in the developing world.

    But, let's address your final claim that this is having fun while others suffer. That's simply not accurate and is missing the point. When the Apollo moon landings happened, people in poor areas crowded around the few radios they had to listen in. Why? Because as badly off as they were, they understood that some things really are achievements for humanity as a whole. In the long run, we're going to need to colonize space. And we'll need to be ready for it. Moreover, we have a real reason to figure out how common life is- for some reason there's almost no intelligent life out there. We need to figure out, for the good of humanity as a whole, if the Great Filter preventing the rise of intelligent civilizations http://en.wikipedia.org/wiki/Great_filter is ahead of us or behind us. I suspect that most of it is behind us, but if there's any in front of us, it needs to appear before space travel becomes cheap or easy. The more we know about how common life is, what kinds of life evolve, and other related issues, the better understanding we get of whether we need to be prepared for possible filtration up ahead. This is for the good of humanity as a whole.

  5. Re:Is there any other evidence? by ColdWetDog · · Score: 5, Insightful

    They really should do proper science and wait for something more concrete, such as spectroscopic data, before making such announcements.

    What exactly do you think they did? Re read Kim Stanley Robinson? Yes, their is spectroscopic data that supports the ideas, yes they need to do more it.

    Proper science isn't waiting until you know everything. That never happens anyway.

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