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Mars Space NASA

Phoenix Mars Lander Deploys Robotic Arm, Possibly Finds Ice 168

Posted by Soulskill from the armed-and-gregarious dept.
The Phoenix Mars Lander has successfully deployed its robotic arm and tested other instruments including a laser designed to detect dust, clouds, and fog. The arm will be used to dig up samples of the Martian surface, which will be analyzed as a possible habitat for life. A camera on the arm will allow pictures to be taken of the ground directly beneath the lander. The camera has already seen what may be ice, which was exposed when the soil was disturbed by the landing. The data collected by the arm will be compared to recent findings which suggest that water on Mars may have been too salty for most known forms of life.
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Phoenix Mars Lander Deploys Robotic Arm, Possibly Finds Ice More

Phoenix Mars Lander Deploys Robotic Arm, Possibly Finds Ice

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  • I only hope... (Score:2, Interesting)

    by Tubal-Cain ( 1289912 )
    ...that this lander does as well as the other two.

  • Could be, could not be... (Score:5, Funny)

    by lazy_nihilist ( 1220868 ) on Friday May 30, 2008 @07:43PM (#23605913)
    Lets wait for the test data to confirm if it is ice. For all we know it "could" be oil ;-)

  • Extremophiles (Score:5, Insightful)

    by Gothmolly ( 148874 ) on Friday May 30, 2008 @07:46PM (#23605953)
    Just because its too salty for 'most' life doesn't mean its too salty for ANY life.

    • Re:Extremophiles (Score:5, Informative)

      by spyder913 ( 448266 ) on Friday May 30, 2008 @07:52PM (#23606017)
      "The scientists say that the handful of terrestrial halophiles -- species that can tolerate high salinity -- descended from ancestors that first evolved in purer waters. Based on what we know about Earth, they say that it's difficult to imagine life arising in acidic, oxidizing brines like those inferred for ancient Mars."

      Looks like it is just very unlikely with what we know.

      • Re: (Score:2, Funny)

        by Anonymous Coward
        It's life Jim, but not as we know it

      • Re:Extremophiles (Score:4, Insightful)

        by symbolset ( 646467 ) on Friday May 30, 2008 @08:21PM (#23606251) Journal

        Based on what we know about Earth, they say that it's difficult to imagine life arising in acidic, oxidizing brines like those inferred for ancient Mars.

        er, ahem -- [enotes.com]

        Hamlet:

        And therefore as a stranger give it welcome.

        There are more things in heaven and earth, Horatio,

        Than are dreamt of in your philosophy.

        Hamlet Act 1, scene 5, 159-167

        Wm. Shakespeare

        Two billion years from now it may be difficult to imagine life evolving on the Earth. If you can still find the Earth, that is. Time has a way of hiding things.

        • Two billion years from now it may be difficult to imagine life evolving on the Earth. If you can still find the Earth, that is. Time has a way of hiding things.
          OT but in Harry Harrisons Stainless Steel Rat books people from 30000 years in the future are puzzled as to why the name of the ancestral home planet of humanity translates as "Dirt".

      • Re: (Score:2, Funny)

        by AmigaMMC ( 1103025 )
        "The scientists say that the handful of terrestrial halophiles"

        People who play too much on the Xbox?

      • Re: (Score:2, Insightful)

        by Tablizer ( 95088 )
        ["The scientists say that the handful of terrestrial halophiles -- species that can tolerate high salinity -- descended from ancestors that first evolved in purer waters. Based on what we know about Earth, they say that it's difficult to imagine life arising in acidic, oxidizing brines like those inferred for ancient Mars."] Looks like it is just very unlikely with what we know.

        I don't see how we can read much into that. Evolution on Earth just found it quicker to start one place/niche and shift to anothe

      • Re: (Score:2)

        by instarx ( 615765 )

        "The scientists say that the handful of terrestrial halophiles -- species that can tolerate high salinity -- descended from ancestors that first evolved in purer waters. Based on what we know about Earth, they say that it's difficult to imagine life arising in acidic, oxidizing brines like those inferred for ancient Mars."

        Looks like it is just very unlikely with what we know.

        And 20 years ago they would have said that it was difficult to imagine finding life in water above 212F, yet we have found bacteria in the deep-sea vents that require those temperatures and die if cooled. Don't give up hope yet.

    • Re: (Score:2)

      by geekoid ( 135745 )
      And nobody said that, just for known life.
      Considering it's composition, it would need to be some particularly weird as shit. Possible so weird we couldn't recognize it.

    • Re:Extremophiles (Score:5, Insightful)

      by v1 ( 525388 ) on Friday May 30, 2008 @08:08PM (#23606157) Homepage Journal
      We keep seeing these same generalizations going on when looking for life elsewhere.

      Lets face it, odds are if we DO find life, it's going to be fundamentally different than what we're expecting it to be. Saying conditions aren't good for life anywhere based on what we consider habitable is silly. The reason our conditions are ideal for our life isn't because we got lucky and got the right combination of environment to grow up in, it's because we adapted to become the best suited for the environment we developed in.

      I'll give them "initial conditions" though. Certain environments certainly lower the odds for genesis. Once you've achieved genesis however, evolution takes over, and so long as you don't have a fast severe change in conditions, life will adapt over time to become well-suited to whatever the environment can throw at it.

      So unless you're looking for life that has just recently come to be, there's almost no point in examining conditions. Probably the only environmental necessity is reasonable temperatures. (and I mean very generous range, at least a ways over abs 0 and too low to melt lead)

      Actually, on the high end, it would not completely surprise me to find life IN a sun. Whenever we look somewhere and say no life can exist there, it's too hot, too cold, too alkaline, too dry, whatever, we end up finding life. Recently we found life IN a rock, eating radioactivity. After that you pretty much have to be an optimist.

      • Re:Extremophiles (Score:5, Interesting)

        by Kjella ( 173770 ) on Friday May 30, 2008 @08:31PM (#23606331) Homepage
        Well, on the other hand you can argue that if there was a niche here on earth life would have evolved to fit it given the obvious benefits like having no enemies. So if we don't find life here on earth, are chances really that great that we'll find radically different life living under the same conditions on other planets? I suppose that's a difficult question, since it's hard to tell how much evolution is path-dependent or if the same basic creatures would form anyway.

      • Re:Extremophiles (Score:5, Insightful)

        by maxume ( 22995 ) on Friday May 30, 2008 @08:39PM (#23606385)
        What are you expecting life elsewhere to be? I'm expecting it to be something that takes advantage of energy gradients (food is essentially an energy gradient, it takes less energy to gather fruit than the fruit contains, similarly for prey) in order to maintain its own order at a level above that of the average environment that it exists in.

      • Re:Extremophiles (Score:5, Informative)

        by DerekLyons ( 302214 ) <fairwater@@@gmail...com> on Saturday May 31, 2008 @12:38AM (#23607455) Homepage

        Lets face it, odds are if we DO find life, it's going to be fundamentally different than what we're expecting it to be.

        You state that as if it were a fact, rather than the opinion it actually is.
         
         

        Saying conditions aren't good for life anywhere based on what we consider habitable is silly.

        They aren't saying conditions are good for life based on what we consider habitable. They saying conditions are good for life based on the laws of physics and chemistry and reasonable extrapolations from the same.

      • Re: (Score:3, Insightful)

        by MichaelSmith ( 789609 )

        Once you've achieved genesis however, evolution takes over, and so long as you don't have a fast severe change in conditions, life will adapt over time to become well-suited to whatever the environment can throw at it.
        This is why I think martian life would be obvious to us if it existed. The fact that we have to hunt around for it strongly suggests to me that it doesn't exist.

        • Re: (Score:3, Interesting)

          by v1 ( 525388 )
          That's a good point I hadn't considered - life will tend to terraform an environment. Earth offers a much greater variety of environments than mars, and among them there are very few places where it's hard to identify the presence of life even with only casual observation. If there were life on mars, it would be everywhere since conditions are so similar everywhere and very little additional evolution would be required to colonize.

          I think what they're looking for is the past presence of life. Hoping perh

      • Re: (Score:2)

        by imipak ( 254310 )

        Lets face it, odds are if we DO find life, it's going to be fundamentally different than what we're expecting it to be.
        [ CITATION NEEDED ]

        Seriously, what evidence do you have to back up your assertion?

    • Re:Extremophiles (Score:4, Insightful)

      by jd ( 1658 ) <imipak@ y a hoo.com> on Friday May 30, 2008 @08:17PM (#23606231) Homepage Journal
      You are correct. Although it has been pointed out by others that terrestrial lifeforms that handle extreme salinity first evolved in purer waters, this doesn't tell us a whole lot, as water at extreme depths may well be extremely pure, with life migrating towards the surface as it became more tolerent of conditions. Also, knowing it was salty at one point in time does not tell us about salt levels prior to this, or indeed about salt levels anywhere on Mars outside of the points so far examined. All this also assumes a traditional carbon-based lifeform, which although the most likely, is not guaranteed to be the only form of life. Silicon is a strong contender, particularly if you have environments in which carbon-based structures would be less likely to survive.

      In short, we could easily dream up a million and one scenarios in which life could have existed on Mars or could exist there today. Without more information, all we can say with any certainty is that terrestrial life could not have arisen on the surface of Mars within the narrow region of space and time for which we have reliable geological data. We can say nothing about any other form of life, any other location on Mars, or any other point in Martian history.

      (God, I hate agreeing with someone who's got me marked as a foe. It's so... so... Un-Slashdotish, somehow.)

      • Re: (Score:3, Funny)

        by ConceptJunkie ( 24823 )
        (God, I hate agreeing with someone who's got me marked as a foe. It's so... so... Un-Slashdotish, somehow.)

        Perhaps you should have appended "you insensitive clod!" to your post.

      • Re: (Score:2)

        by mrmeval ( 662166 )
        Great Salt Lake is at a water activity of 0.75 at 30 percent salt solution and has life.

        http://biology.fullerton.edu/biol302/envir.html [fullerton.edu]

        It's still dependent on an ecosystem. If anything could possibly be alive there it would be eating leftovers. I pity the first people to go there because they'd NEW FOOD. ;)

      • Re: (Score:3, Interesting)

        by smaddox ( 928261 )

        Silicon is a strong contender
        Unlikely. Carbon oxidizes into a gas over the range of temperatures we are talking about, whereas Silicon oxidizes into a solid. The former has the advantage of removing carbon from the system - allowing for energy to be gained without a separate process for waste removal.

        That is just one example. I'm not saying it is impossible, but there are reasons life is carbon based. It isn't arbitrary.

    • Re:Extremophiles (Score:5, Informative)

      by AySz88 ( 1151141 ) on Friday May 30, 2008 @09:06PM (#23606509)
      I took a course with Steve Squyres [wikipedia.org] (the principal investigator for the rover mission) in the fall semester. According to him, you can't look to Earth extremophiles as evidence that life can arise in these conditions. Extremophiles apparently all have adaptations such that, inside their cells, they can do their chemistry in 'normal' (non-acidic, non-salty, ...) conditions. If life were to arise in extreme conditions, they'd probably need totally different chemistry.

      There's certainly a possibility of some exotic form of life arising in extreme (for us) conditions, but we shouldn't be expecting it to be possible, as there's no evidence that it can happen.

    • Re: (Score:2, Interesting)

      by AmigaMMC ( 1103025 )
      Exactly! When are we going to get rid of this narrow minded, human-mind driven beliefs that life has to look and act like what we know to consider it life? Just a few weeks ago scientist found another life form here on Earth living at more extremely high temperatures than ever before. Who knows what's out there...

      • Re: (Score:2)

        by smaddox ( 928261 )
        Science has the characteristic of making predictions based on current knowledge. To the best of our knowledge, it is unlikely that life would arise in such extreme conditions. However, that is only a hypothesis, and in order to attempt to prove it wrong we are performing experiments.

        You aren't the first person to consider an alternate hypothesis. Many people with much more knowledge of this topic have considered the possibility, and determined it to be of low probability. However, we do not have enough info

  • The Red Planet (Score:5, Funny)

    by StaticEngine ( 135635 ) on Friday May 30, 2008 @07:48PM (#23605973) Homepage
    Salty. Red. Once covered in liquid.

    It's clear to me that Mars was once a giant Bloody Mary for the gods. It's the only explanation that fits.

    I love science!

  • Go halophiles! (Score:2, Insightful)

    by Anonymous Coward
    "... compared to recent findings which suggest that water on Mars may have been too salty for most known forms of life."

    Sure, but don't count the halophiles out [wikipedia.org]. Happy in 2 Molar salt solutions? Wow.

    • Re: (Score:2, Informative)

      by Anonymous Coward
      The supposed salinity of the water on Mars is much higher than any halophile could survive.

  • Apologies to Mr. Bradbury... (Score:3, Funny)

    by Tastecicles ( 1153671 ) on Friday May 30, 2008 @08:07PM (#23606141)
    ...if they'd landed a couple kilometres to the West, they'd've landed in the middle of the town square...

  • Comment removed (Score:3, Insightful)

    by account_deleted ( 4530225 ) on Friday May 30, 2008 @08:08PM (#23606153)
    Comment removed based on user account deletion

    • Re:"Most known forms of life"? (Score:5, Funny)

      by alexborges ( 313924 ) on Friday May 30, 2008 @08:44PM (#23606421)
      Being a PolSci graduate does not make you a politician.

      It makes you, very probably, a pothead, a great guy to converse with.... and a somewhat disturbing character since youre posting on slashdot.

      Now "saying blatant things about science without knowing anything you talk about", THAT makes you a politician.

    • Re: (Score:2, Redundant)

      by gatkinso ( 15975 )
      >> Why are we constantly relying on Earth standards to predict what life on an other planet requires?

      Thinking about this question for all of one half of a second, I can only come up with the answer that Earth based life is the only type of life we have ever encountered.

      Maybe, just maybe, this is why we use that metric.

      Do we (meaning those who truely contemplate such things) know that this is a narrow window in which to frame our query? Yes. Contrary to your beliefs, this has occurred to people other

    • Re: (Score:2)

      by blueg3 ( 192743 )
      Because there's no way to predict in advance what something that we have absolutely no experience with (life that is in no way like any form of life on Earth) would be like. As such, looking for radically different life is like looking for "anything" -- it's not very productive.

  • If NASA Wanted Ice . . . (Score:5, Funny)

    by hardburn ( 141468 ) <hardburn.wumpus-cave@net> on Friday May 30, 2008 @08:09PM (#23606167)

    . . . I could have given them some.

  • Granades! (Score:3, Funny)

    by alexborges ( 313924 ) on Friday May 30, 2008 @08:40PM (#23606393)
    Why dont they put some granades on those robots so we can beat the shit out of those red-commie-martians?

    Hell, I bet they are ay-rabs as well with all that sand arround and all.

    Perhaps they have WMD's as well!

    And also, if a big hit as the landing "uncovered" ice, well the granades could be of certain scientific use....

  • Might have found ice? (Score:5, Insightful)

    by exp(pi*sqrt(163)) ( 613870 ) on Friday May 30, 2008 @08:41PM (#23606401) Journal
    Before the lander even took off, we all knew it might find ice. Now it's landed there's a press release saying it might have found ice. Is there any news content here? Maybe what's different is that previously we knew it might have found something that might be ice, but now it's definitely found something that might be ice. But previously we also knew it might have found something that was definitely ice. Might be definitely, definitely might be? Please, someone wake me when it's definitely definite.
    • Wake up! It's definitely definite that maybe it's ice!

    • Re: (Score:2, Insightful)

      by felipekk ( 1007591 )
      Maybe you shouldn't have read the article.

      But definitely definite you shouldn't have posted...

    • Re: (Score:2, Insightful)

      by Anonymous Coward

      Please, someone wake me when it's definitely definite.

      What are you, a Creationist? :)

      Seriously -- Science Doesn't Work Like That, and deep down inside, you know it.

      When I was a kid, there "might" have been water or CO2 in the polar caps. All we knew was what we could see from telescopes: the Martian poles had whitish stuff on them that got bigger and smaller over the course of the Martian year.

      Science works by changing those "might"s into "probably"s and "almost certainly"s, but there's almost nev

      • Re: (Score:3, Insightful)

        by exp(pi*sqrt(163)) ( 613870 )
        > A few days from now, I'll bet you we'll know there'll definitely be ice on Mars.

        Clearly the information from this probe is of no use to you. You know the answer already. But I'm still waiting.

  • Disturbed by the landing? (Score:5, Interesting)

    by bchernicoff ( 788760 ) on Friday May 30, 2008 @09:53PM (#23606739)
    The camera has already seen what may be ice, which was exposed when the soil was disturbed by the landing.

    I have been wondering about this. I'm sure NASA would have taken into consideration that the retro rockets firing as it landed might melt ice and/or destroy signs of life. Right?

    • Re:Disturbed by the landing? (Score:5, Informative)

      by Brett Buck ( 811747 ) on Friday May 30, 2008 @10:04PM (#23606775)
      Yes. The chances of destroying life that can withstand extremely high radiation levels, a virtual vacuum, and living in frozen C02 is unlikely to be bothered by a little bit of ammonia steam for a few seconds. Additionally the design intentionally spreads the plume over a wide area to lower the local heating, pressure, or contamination effects. Melting ice isn't likely given the small heat input and short duration, but it's not clear that melting a little bit of ice for a few seconds before it refreezes actually hurts anything much.

                    Brett

      • Re: (Score:3, Interesting)

        by justinlee37 ( 993373 )
        But shouldn't the sample still be collected from a different spot? I don't think we're worried about hurting the Martian ecosystem here or anything, we just want accurate samples.
        • Oh, of course, they are going to select what they think are the cleanest possible samples for the chemical analysis, and they already know how to subtract out the engine residue (mostly ammonia but also raw hydrazine) from the results. They have thought of these sorts of things (and did on Viking, as well).

                    Brett

    • Re:Disturbed by the landing? (Score:5, Informative)

      by DerekLyons ( 302214 ) <fairwater@@@gmail...com> on Saturday May 31, 2008 @12:43AM (#23607477) Homepage

      The camera has already seen what may be ice, which was exposed when the soil was disturbed by the landing.

      I have been wondering about this. I'm sure NASA would have taken into consideration that the retro rockets firing as it landed might melt ice and/or destroy signs of life. Right?

      Yes. The retrorockets are designed to produce minimal contamination and/or disturbance. (And they shut off a couple of meters above the ground to further reduce the effects.) The arm is designed to dig down well below the expected penetration level of any contamination or disturbance.

      • And they shut off a couple of meters above the ground to further reduce the effects

        Strange that they got so much dirt on the pads then. From the Phoenix landing press kit [nasa.gov][pdf]:

        By the time the lander gets to about 30 meters (98 feet) above the surface, it will have slowed to about 2.4 meters per second (5.4 miles per hour) in vertical velocity. Continuous adjust- ments to the thruster firings based on radar sensing will also have minimized horizontal veloc- ity and rocking. Touchdown will be about 12 seconds away. For that final piece of the journey, Phoenix will maintain a steady des

    • Re: (Score:2)

      by imipak ( 254310 )
      Yes; however (a) these are pulsed thrusters, with a very low (individual) power output, as thrusters go; (b) vertical vector velocity at touchdown is roughly 5mph, and (c) the thrusters cut out instantly at touchdown.

      What does seem to have happened, interestingly, is that the upper couple of centimetres of dustry regolith has been blown clear in a big patch directly below the lander [photobucket.com]. The arm is designed to be able to reach down and image the underside (so that they can be sure all three landing pads are s

  • I know this is important to geek news and all, but Slashdot is treating the Phoenix like their firstborn.

    "Phoenix started walking today!"

    "Phoenix said his first word today!"

    "Phoenix poopied like a big boy today!"

    • Dude, have you watched the NASA ubergeek reactions every time a space mission hits a milestone? Slashdot is the varsity football team at a high school kegger in comparison.
  • "recent findings which suggest that water on Mars may have been too salty for most known forms of life"

    Genuine question - if the water is too salty, wouldn't organisms have evolved over the millenia that could survive in that environment?
  • The data collected by the arm will be compared to recent findings which suggest that water on Mars may have been too salty for most known forms of life.

    What about most unknown forms of life?

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