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Can any life survive without water?

  1. Aug 30, 2004 #1
    Can any life survive without water? If not, why?
     
  2. jcsd
  3. Aug 30, 2004 #2
    I think so, because NASA Scientists know that Neptune has a Methane atmosphere & they also think there maybe some sort of organic life there, & i think the same is true for Titan too.
     
  4. Aug 30, 2004 #3
    I know a lot of astrobiologists believe that they only reason “all life as we know it“ depends on water is simply because we’ve evolved with water in our environment. If an organism were to evolve in an environment with some other solvent (some acid perhaps) it would not require water at all.
     
  5. Aug 30, 2004 #4

    Moonbear

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    From the above posts, I guess that requires refining the question. Do you mean known organims? Or do you mean could it be possible for some undiscovered life form?
     
  6. Aug 31, 2004 #5
    i think so . I think the other planet's species may survive without water. Because the other planet has no water so there will create some species do not need water.
     
  7. Aug 31, 2004 #6

    LURCH

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    Undiscovered. All lifeforms so far discovered use H2O. In theory, it is possible for some other chemicle reaction to produce enegry for life-processes, but this has never been observed.
     
  8. Aug 31, 2004 #7

    Moonbear

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    Lurch, that's why I was asking. It wasn't clear from the original question whether the remainder of the answers were what phenylalanine was looking for.

    However, because other planets in our solar system don't have water, it doesn't mean that if life ever existed on those planets that it didn't also require water. Some of those planets have water in frozen form or vapors. Part of the Mars exploration was to look for signs of life forms because the geography/topography of the planet suggested there once was water there. :rain:

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    :thumbs_up: Like the new smilies.
     
  9. Aug 31, 2004 #8

    Monique

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    So which other solvent would be a good candidate to support life?
     
  10. Aug 31, 2004 #9
    Ammonia as a life-supporting solvent

    Ever since Haldane suggested it, ammonia has been a favorite alternative solvent candidate of science fiction writers.


    • In 1954, J. B. S. Haldane, speaking at the Symposium on the Origin of Life, suggested that an alternative biochemistry could be conceived in which water was replaced as a solvent by liquid ammonia.

    But, then, ammonia molecules are mostly hydrogen (by number of atoms). I don't know of any non-hydrogen solvents that might substitute for water.
     
  11. Aug 31, 2004 #10
    From what I know, the two "best" possible candidates for alternative biological solvents are (as mentioned above) ammonia (NH3) and methanol (CH3OH).

    Although I've read somewhere that hydrogen sulfide (H2S) may be a good analouge to water. But the problem is that Sulfur is much more rare than oxygen and that H2S tends to break down to its atoms failry easily.
     
  12. Aug 31, 2004 #11

    Monique

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    Which (top 5) substances have the highest dipole moment / dielectric constant?
     
  13. Aug 31, 2004 #12
    Life, as we know it, needs a dipolar solvent.
    Life, in other form could need any solvent, even non-polar. We risk of thinking on life from a "Earth-centric" viewpoint.
     
  14. Sep 1, 2004 #13

    Phobos

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    Welcome to Physics Forums, all you new members! :smile:

    Just to nitpick...
    Scientists hope to find signs of life elsewhere in the solar system, but so far they have no evidence to indicate that there actually is (or was) life elsewhere (i.e., it's possible, but not yet found).

    Keep an eye on NASA/ESA's ongoing Cassini mission to Saturn/Titan! Although it is probably not equipped to detect life directly, the mission will be taking a close-up look at Titan, which is as you suggest, one of the moons being eyed for signs of life.
     
    Last edited: Sep 1, 2004
  15. Sep 1, 2004 #14
    This question is so important that every time I think of it my stomarch just begins to inflate to the size of a football. It is not that life entirely depends on water, our FALSELY CONSTITUTED SENSE OF NORMALITY is causing us to think so. How can we think that life without water is impossible? It is not only wrong and dangerous to think so, but actually it is suicidally so. Every time I think of the fate of the dinoseurs, it immediately shakes my intellect as to why we must not think the way we now do. Universally, and yet very scientifically, mulitple surviving conditions exist in abundance.

    ERROR OF JUDGEMENT

    Nearly 100% of science seems to be concentrating on finding life conditions in the universe based on water. NASA of all the institutions on this planet have sent missions after missions to many planets in search of water-based life conditions. What about other life forms devoid of water bases? Why does science take this pathway to progressive discoveries? Why not widen your horizon?

    THE PRINCIPLE OF DANGEROUS CONTENT that I mentioned in many places in this physics forum and elsewhere on the internet was deduced from many years of my thinking about water and its logical and quantitative implications to the human life. The multiple levels of the human dependence on water for its countless uses is precisely what I am talking about here. Yes, water is a big problem, however, my studies also show that water is not the only culprit. Apart from water, we naively depend on countless external utilities for survival......from tables, pencils, to food, heat, etc......all numerically measured in moderate doses. Why? Why must we always think and act in this way when we are already naturally empowered to THINK and ACT otherwise? Frustratingly, this has left me with an inevitable conclusion that we are better off concentrating on the 'SCIENCE OF MAN' than on the 'SCIENCE OF NEEDS'. Well, I leave this to everyone's conscience.
     
    Last edited: Sep 1, 2004
  16. Sep 2, 2004 #15

    Phobos

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    Why not learn to walk before you learn to run? Life as we know it depends on water. This is a logical starting point for searching for other life, especially when dealing with limited resources (e.g., NASA/ESA, SETI funding). The idea of life without water is not ruled out. If we detect signs of life in a place with no water, then we can expand our exobiology search.
     
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