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Life on moon?

  1. Oct 24, 2007 #1
    I dont know too much about astronomy, so my question may seem like a dumb one to you guys. I heard that its been speculated that the earth's moon has lunar ice. if it does, then it has water, which is a necessary component for a planet or moon to sustain life, just like if mars had water, it likely supported life. But if the moon has lunar ice, how come no one's really talking about the possiblilty of life on the moon? there all this hype about how mars may have suported life. is it because of the moon's distance from the sun, or what?
  2. jcsd
  3. Oct 24, 2007 #2
    It needs to be liquid.
  4. Oct 25, 2007 #3
    If I'm not mistaken some 'extremophiles' can exist in ice.

    I would say the problem with life on the moon would be related to the fact it has no atmosphere.

    No atmosphere means no aerobic organisms. Also, no protection from UV micrometeor bombardment.
  5. Oct 25, 2007 #4
    Ice is a solid. No life can start up in a solid, though some life can survive being frozen.
  6. Oct 25, 2007 #5
    There is scientific evidence that life cannot start up in a solid since there is no scientific evidence for how life started up at all. The first organisms to inhabit the earth were the simplest microorganisms, whose fossil record is much less accurate than larger organisms.

    Whether life can or cannot start in ice remains purely speculation. Just because there are no examples of it happening on the Earth (that we have been able to discover) does not rule out the possibility of its occurence.
  7. Nov 10, 2007 #6
    That's silly, the entire reason water is considered to be a precursor to life is because of its properties as a liquid. In order for 'life' to exist, it has to grow, reproduce, eat, etc...

    You cannot achieve ANY of the properties of life as a solid. The only possible way would be if there existed gaps within the ice, in which case life would not be developing from the ice itself but from the cracks.
  8. Nov 14, 2007 #7
    "Life as we know it Jim" (Startrek) is based on water, but perhaps there are other lifeforms in our part of the galaxy.
  9. Nov 14, 2007 #8


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    Surely it can't be that reason!

    The moon is relatively the same distance from the sun as we are. If there were any problems regarding distance, it would be that of Mars and not the Moon.
  10. Nov 21, 2007 #9
    Life has been found at the bottom of the oceans in really terrible (what we think impossible) conditions, so it is always possible that life can exist in other forms and not need the things which we need to survive.

    To say that live cannot exist in ice means that a) we have not found any evidence to show that it can exist in ice, and b) that we are unwilling to consider other possibilities.

    Bacteria and viruses can live in all kinds of conditions or they can hibernate waiting for the right trigger to happen to bring them back to 'life'. That trigger could be absolutely anything, from solar radiation of a particular frequency, to being brought out into an atmosphere full of methane etc.

    Personally, I dont know what kind of sleeping organisms might be inside the moon rocks, or inside falling asteroids which do not burn up, and get to land in our atmosphere. It is only a matter of time before something is found that does not originate from here, and when it does, we better be ready to think outside the box. You scientific guys will be at the front line.
  11. Nov 21, 2007 #10


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    But it in that case there is no need for the ice! Otherwise the arguement is a bit circular:
    Life evolved in water -> water is a good place to look for life -> ice is water -> therefore ice can have life.
    But since we haven't found life that lives in ice (rather than merely being able to survive being temporarily frozen) there is no reason to regard ice as an indicator of life.

    You might as well say tungsten is an indicator of life, just because we haven't found life based on tungsten doesn't prove there isn't any!
  12. Nov 21, 2007 #11
    So is it just the high winds that makes rocks move in the deserts?

    If we ever find life in the universe, it is possible that it is not based on water. Just because we are based in a water environment, does not mean that all other life forms (if there are any) have to be.
  13. Nov 24, 2007 #12


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    This is completely true. However, science has to be based on obseravtion. As mgb phys said, there is no limit to where we could search for life, unless we ourselves set a limit (we don't look for signs of tungsten). The only clues we have to go on are the kinds of life we have discovered so far. Also, the OP was about the imoprtance of finding ice, because it is a form of water.

    All life we have ever seen coincides with the presence of liquid water. That is the only reason we look for water when searching for life. This doesn't mean that life can't exist in any other environment, it just means we would have no idea how to look for that kind of life. E.g., cuold the complex magnetic fields of the sun organize coherent structures of sentient plasma? We don't know. More importantly, we can't know. There is no way of looking for that, since we have no clue what it might look like. We have to keep the search down to something we have a reasonable chance of recognising, if we spot it. And that means we have to look for life based on the interactions of oxygen, carbon, and liquid water; it's all we know.
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