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Mars Space NASA Science

Water Flowed Recently on Mars 411

elfguygmail.com writes "According to to Space.com 'Small gullies on Mars were carved by water recently and would be prime locations to look for life, NASA scientists said today.' "
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Water Flowed Recently on Mars

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  • by Tanjou ( 83126 ) on Thursday August 25, 2005 @02:04PM (#13400051)
    Is this another instance of "recently" meaning "within the last 1,000,000 years?" ...recently is since the last episode of Family Guy.
    • You beat me to it, I was going to ask the same question. I hate the use of the word recently to refer things happened more than a million years ago.
    • Re:How recently? (Score:2, Interesting)

      by OnceDark ( 155468 )
      The article states:

      The new study suggests water may still bubble to the surface of Mars now and then, flow for a short stretch, then boil away in the thin, cold air.

      That would seem to suggest that "recently" may well be right at this moment.
    • Re:How recently? (Score:5, Insightful)

      by justforaday ( 560408 ) on Thursday August 25, 2005 @02:13PM (#13400171)
      As has been said, "recent" is in geologic terms. And plantery scientists are geologists. They don't ask you CS guys to change your terminology to better suit the terms that they think in. Well, maybe they do, but you guys still don't do it...
      • As has been said, "recent" is in geologic terms.

        So when my boss says I'll get a raise "soon", then he too, must be thinking in geologic terms. That would certainly explain a lot - I just thought he didn't want to give me a raise; I didn't consider that we might be using two different timelines...:)

    • The gullies may be sites of near-surface water on present-day Mars and should be considered as prime astrobiological target sites for future exploration," said Jennifer Heldmann.

      I asked myself the same question. Recently as in the last 100 centuries, or 100 days? I take the above quote to mean the latter.

    • by the_mighty_$ ( 726261 ) on Thursday August 25, 2005 @02:51PM (#13400565)

      I dont know. I find it frustrating that the article provides just about no details. However, I did a quick Google search, and came up with this:

      http://www.msss.com/mars_images/moc/june2000/ [msss.com]

      And:

      http://www.space.com/scienceastronomy/solarsystem/ mars_ice_signs_010614.html [space.com]

      The first page is dated in the year 2000! I wonder if this is really news after all! The second page is dated 2001. It states basically the same thing as the article the submitter linked to, however it says how long ago "recent" is--10,000,000 years!!

      • by youta ( 900287 ) on Thursday August 25, 2005 @02:58PM (#13400633)
        The first page is dated in the year 2000! I wonder if this is really news after all! The second page is dated 2001. It states basically the same thing as the article the submitter linked to, however it says how long ago "recent" is--10,000,000 years!!

        If 10,000,000 is "recent", then 2005 vs 2000 is still breaking news. :P
  • Article Text (Score:5, Informative)

    by Anonymous Coward on Thursday August 25, 2005 @02:05PM (#13400067)
    Water Flowed Recently on Mars, NASA Scientists Say
    By Robert Roy Britt
    Senior Science Writer
    posted: 24 August 2005
    07:57 pm ET

    Small gullies on Mars were carved by water recently and would be prime locations to look for life, NASA scientists said today.

    There have been many studies of Martian gullies that concluded water was involved. But most of the features are ancient, or if they seemed modern then there were questions about how the water could stay liquid long enough to do the carving.

    Scientists know there is a lot of water ice on Mars, locked up at the poles and beneath the surface elsewhere.

    Water is a key ingredient for life as we know it, and other scientists have speculated that life on Mars, if there is any, could lurk just beneath the surface where ice melts in pockets.

    A closer look

    The new study suggests water may still bubble to the surface of Mars now and then, flow for a short stretch, then boil away in the thin, cold air.

    The conclusion is based on computer modeling of the atmosphere and how water would behave.

    "The gullies may be sites of near-surface water on present-day Mars and should be considered as prime astrobiological target sites for future exploration," said Jennifer Heldmann, the lead researcher from NASA's Ames Research Center. "The gully sites may also be of prime importance for human exploration of Mars because they may represent locations of relatively near surface liquid water, which can be accessed by crews drilling on the red planet."

    Any potential long-term human presence on Mars would require a water source, both for drinking and to be broken down into hydrogen as fuel for return flights.

    The claim that water carved the gullies is based on the shape and size of features spotted by NASA's Mars Global Surveyor.

    Short gullies

    "If liquid water pops out onto Mars' surface, it can create short gullies about 550-yards (500-meters) long," Heldmann said in a statement. "We find that the short length of the gully features implies they did form under conditions similar to those on present-day Mars, with simultaneous freezing and rapid evaporation of nearly pure liquid water."

    Some of the gullies taper off into very small debris fields or leave no debris at all. That implies the water rapidly froze or evaporated.

    Given the low air pressure on Mars, water would boil in a flash, the researchers say, so it is doubtful that ice accumulates in the gullies.

    The findings will be presented next month at a meeting of the American Astronomical Society's Division for Planetary Sciences in Cambridge, England.
  • Documentary (Score:3, Funny)

    by exi1ed0ne ( 647852 ) <exile@pessimist[ ]et ['s.n' in gap]> on Thursday August 25, 2005 @02:08PM (#13400105) Homepage
    Of course they have - The whole core is ice!! [imdb.com] Now, hot looking mutants is the find I'm looking for!
  • by Elrac ( 314784 ) <carl@EEEsmotricz.com minus threevowels> on Thursday August 25, 2005 @02:16PM (#13400200) Homepage Journal

    I was a little disappointed to find no mention in TFA about what they meant by "recently". 1 year? 5? 10? 100? 1000? 10K?

    Many will be thinking, water == life!. Let's say this improves the possibility, but if most water on Mars is (and especially, was) mostly locked up as ice and/or only very ephemerally available, then I'd say it's much less likely that the "long shot" of evolution that led to our existence on Earth could have taken place similarly on Mars. Our planet spent millions of years two-thirds covered in water and under a dense methane-ammonia atmosphere. In contrast, it seems Mars had far less soup under far less atmosphere at (average) somewhat lower temperatures. I guess the only thing Mars might have had more of, sans an atmosphere of effective sunscreens, is ionizing (and hence mutagenic) radiation.

    • by Cally ( 10873 )

      I was a little disappointed to find no mention in TFA about what they meant by "recently". 1 year? 5? 10? 100? 1000? 10K?

      I hate to disabuse you, but you're out by a couple of orders of magnitude. 10 million years is considered "recent" in the context of Martian geology and landscape morphology. Nothing much is thought to have happened (except in the sense of very slow processes, such as air-borne dust particle erosion, the occasional impact and periodic outbursts of sub-surface ice as water which immedia

  • by SilentReallySilentUs ( 908879 ) on Thursday August 25, 2005 @02:17PM (#13400204) Homepage
    Water straight from the untouched springs of Mars! Fabulous!
  • Likely For Life If (Score:3, Interesting)

    by chydnonax ( 820552 ) on Thursday August 25, 2005 @02:22PM (#13400263)
    These gullies are likely to harbor life only if there is life under the majority of the martian surface. If it exists just around the poles and under the remnants of old seabeds then NASA would be wasting their time to look for life here. Since NASA cannot know where life is on Mars, if at all, it would do better looking in more likely places like those mentioned above.
    • Life doesn't have to be under most of the surface to exist in a gully like this, it just has to be able to survive an awfully long time without water/other essentials. Just think about bacteria on earth... many those little buggers just go dormant when whatever they need goes away, and then wake back up again when it returns.
    • More likely in caves (Score:5, Interesting)

      by pauljlucas ( 529435 ) on Thursday August 25, 2005 @02:33PM (#13400393) Homepage Journal
      I personally think a good contender for life would be in caves on Mars. There must be plenty of caves in/around either Olympus Mons or in Valles Marineris.

      Why caves? Two reasons:

      1. Here on Earth, there's some pretty "alien" forms of life in caves [pbs.org] that exists in very different and harsh conditions.
      2. On Mars, an ecosystem in a cave would be sheltered from the harsh solar radiation that bakes/sterilizes the surface since there's no protective ozone later.
      Even though Mars is smaller than Earth, the land area is about the same as Earth, so it will take a long time to explore Mars fully.

      I agree that continuing to explore the surface won't lead to much, but there's probably lots of interesting stuff in caves.

  • The new study suggests water may still bubble to the surface of Mars now and then, flow for a short stretch, then boil away in the thin, cold air.

    Ok, if they said liquid hydrogen, or some other such substance I could understand. But why would water boil in cold air, even thin air? First I didn't know Mars had air. Second we have thin air - go to some of the highest peaks on our planet - water does not boil - in fact it should be frozen.

    So would someone explain?
    • IIRC, water boiling isn't a matter of temperature, but rather atmospheric pressure. The less pressure, the lower the temperature for water to boil. That's why water boils more quickly at higher altitudes than at lower altitudes here on Earth. Ever notice most baking goods include alternate baking directions for baking a cake in high altitude?
      • by LionMage ( 318500 )

        IIRC, water boiling isn't a matter of temperature, but rather atmospheric pressure.

        The boiling point of any liquid is a function of both pressure and temperature, a point which you yourself seemed to make later in your post. Check out this article on phase transitions [wikipedia.org] for more technical discussion. (For yet more info, follow the link in the article pertaining to critical points.)

        It's entirely possible for three material phases (solid, liquid, gas) to exist simultaneously for a given substance if you have

    • Thin vs THIN (Score:3, Informative)

      by Gorimek ( 61128 )
      Water doesn't boil in cold air, but it's boiling point is dependent on air pressure. If you're at high altitude you have to boil eggs longer, since the boiling temperature is lower, for example.

      The Martian atmosphere is much thinner than earth's, even at the highest peaks. I think the air pressure at Mt Everest is about 20% of sealevel, while on Mars it is 0.1%.

      I don't have the numbers here, but I assume the physical foundation for this story is that at that pressure, the boiling temperature is below the fr
    • by TCQuad ( 537187 )
      We may have thin air on the top of mountains, but the atmospheric pressure on Mars is 1/150th that of sea level on Earth (as measured by Mariner 4). The triple point of water (when water can equally exist as steam, liquid water or ice) is ~.006 atm (~1/150th of 1 atm) and .0098C. Any temperature on Mars above .01C, therefore, will result in water boiling.
    • by Mr Guy ( 547690 )
      Boiling point is directly related to pressure. As pressure drops, so does the boiling point. That's why you have to be careful of cooking at higher altitudes. In general terms, the lack of air pressure makes things happen at lower temperatures, so things take longer to cook, because even though water is boiling, it's not as hot.

      Or, to think of it another way, the state of matter is a function of how much it gets pushed together. H20 is liquid until it has enough energy for the molecules moving around in
    • Low pressure. Water evaporates (and even boils) in very low pressure. The atmosphere of Mars has very low pressure. So water on Mars would quickly boil away, even though it is cold.

      Also, remember that water turns to a vapor even around its freezing point. Evaporating at cold temperatures isn't out of the ordinary. It seems like an everyday substance to us, but water is incredibly unusual, especially in terms of its volatility.

    • Few things: The atmospheric pressure on mars is only ~10 millibars, whereas earth's atmospheric pressure is ~1000 millibars. That drops water's boiling point to around ~70 celcius. That alone isn't enough to cause the water to boil, I think the parent probably meant "evaporated" or just didn't have all the facts. Water would evaporate more quickly than on earth due to the low pressure, and sublimation. Enough energy from the sun reaches Mars to do that easily.

      Mars definitely does have an atmosphere, check
      • by LionMage ( 318500 )

        The atmospheric pressure on mars is only ~10 millibars, whereas earth's atmospheric pressure is ~1000 millibars. That drops water's boiling point to around ~70 celcius [sic].

        Not sure where you're getting your numbers from, but that's almost certainly wrong. According to this article [wikipedia.org]:

        The boiling point of water is 100 C (212 F) at standard pressure. On top of Mount Everest the pressure is about 260 mbar (26 kPa) so the boiling point of water is 69 C.

        So if the boiling point of water is 69 degrees Celsius at 2

  • Must be me (Score:5, Insightful)

    by $RANDOMLUSER ( 804576 ) on Thursday August 25, 2005 @02:28PM (#13400343)
    Am I the only one who saw this in TFA?

    The conclusion is based on computer modeling of the atmosphere and how water would behave

    In other words "Nothing for you to see here, move along".

  • by ericdano ( 113424 ) on Thursday August 25, 2005 @02:33PM (#13400390) Homepage
    In related news, scientists have discovered that Slashdot.org [slashdot.org] did have a period of time where stories were run without duplicates.....
  • From the article:

    Water is a key ingredient for life as we know it, and other scientists have speculated that life on Mars, if there is any, could lurk just beneath the surface where ice melts in pockets

    What about life as we do NOT know it?

    Most humans are either too ignorant (not stupid) or too arrogant, and think that the only way an organism can 'live' anywhere must be by our own standards as seen on Earth.

    We cannot possibly begin to understand or speculate 'that' which we cannot comprehend. Hu

  • Something tells me that the public opinion of scientists isn't going to be helped by yet another water-on-mars-theory-of-the-week.
  • What I'd be interested in is minerals. I wouldn't send machinery and people there to search for bacteria. I'd send mining robots and automatic transport ground/space vehicles. Then I'd go for the gases on Jupiter.

    Of course if I'd happen to see some crashed alien spaceship, I'd just move along, dropping a few pyromaniacs to enjoy their time :]

  • HUGE IMPACT (Score:3, Insightful)

    by Anonymous Coward on Thursday August 25, 2005 @04:51PM (#13401748)

    Many religious beliefs would be decimated

    Discovery of amoebas on other planets wouldn't necessarily have a big impact on world religions. On the other hand, discovery of intelligent beings on other planets would have a HUGE impact on earth religions, especially if those beings had their own religions or ideas about religion that we could compare and contrast with ours.

    For example, let's say that the aliens also had a religion based around Jesus. That would lend a lot of credibility to Christianity. Or suppose they were very advanced aliens with far superior knowledge of the universe and science, and they told us that all of our religions were superstitious rubbish. I think that would affect a lot of people's beliefs as well.

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