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Aliens/Intelligant Life forms, do they exist?

  1. May 17, 2003 #1
    Do you think that they will ever contact us or vice versa?
    I can`t believe that with all the Trillions of planets there are there is not one planet with remotely the same conditions or atmosphere of earth?
     
  2. jcsd
  3. May 18, 2003 #2

    Phobos

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    Some would say that, with an infinite universe, you're mathematically guaranteed to have another planet like this one.
     
  4. May 18, 2003 #3
    I agree
     
  5. May 18, 2003 #4
    Dig what? In visible universe only we have at least 1021 stars (and many more moons). Can you imagine that they ALL are lifeless? I can't.

    So, there is tons of various lives out there and billions if not trillions of civilized forms. But because they are quite far from each other, chances to communicate (not to say travel) are very slim.
     
  6. May 18, 2003 #5
    Viper - I simple concept. A beautiful concept. Good post man. Let me give you my thoughts on all facets, as alien life to me is a very beautiful thing.

    Statistically, as Alex said, it's incredibally likely. In fact, it's so likely, even I (an anal-retentive logicopath some of you might say) would say it MUST true.

    Will "they" ever contact "us"? Well, I wonder what a statistician would say about this. What's the likelihood (which would require alot of known variables) that "they" would contact "us" in the next 1000 years? 500 years? 10,000 years?

    It's the egocentricity of human nature that makes people absolutely believe that an event that they have emotional investment in MUST happen in their life time.

    Every generation thinks jesus is coming back "in their lifetime". Every generation thinks an atom bomb will go off "in their lifetime" Every generation thinks _____ is the new antichrist. And every generation (for the most part) thinks aliens will come "in their lifetime".

    Recently I've watched man in depth shows on special science channels I get about OUR SOLAR SYSTEM.

    Perhaps, an even better question is to ask:

    Given the evidence that MARS may have water in it, and given the fact that EUROPA (A moon if jupiter) does indeed have an ocean underneath a layer of ice, the ocean and ice of which spread across the entire sphere of the planet - is their multi-cellular life in OUR SOLAR SYSTEM, or HAS THEIR BEEN such life.

    To me, I'd say there must have been single cellular life in our solar system. But that's certianly open for debate.

    Getting to multi-cellular ogranisms is a bit more difficult, shoot it can take a few billion years sometimes!!

    Also, What do we think about life coming to earth via an intercepting object? Anything from a meteor to some long past alien group landing here for a vacation on an intersolar cruise?

    I enjoy talking about space because even with the evidence we have on certain things, it's open to happy debate, and it's all good.!
     
  7. May 18, 2003 #6
    2 cents

    That is not a fact. It is a possibility.
    The facts are: Europa's surface is mostly covered with frozen water. There is a non-water core in Europa. There are sources of energy that could melt some of the ice. We do not know how thick the water-ice is nor if any is melted underneath.

    Keep the change.
     
  8. May 18, 2003 #7
    J-Man, you're incorrect.

    Wave beams have determined that Europa, from the outside towards the center consists of

    1. Ice surface

    2. Ocean in middle

    3. Solid core

    This is new news, that the waves have determined this, so you might not yet be aware.

    But it has been proven
     
  9. May 18, 2003 #8
    Still, life as we know it is pretty hard to make. First, you need the right conditions to make the right amino acids, which in turn need to form the right proteins, which need to go in the correct sequence to form DNA to make cells. And the chances that all this could happen are very small.
     
  10. May 18, 2003 #9

    There are no "right" amino acids.
    There are no "right" proteins.
    There is no "correct" DNA sequence to make cells.

    Furthermore, "life as we know it" doesn't require these things at all. Most yes, but not all.
     
  11. May 19, 2003 #10

    Phobos

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    Hard to conclude that since we just have one example of a success. We don't have any good success-vs-failure data to run any statistics. We don't even know if our closest neighbors (Mars, Venus) have had life or not. And we've only just cleared 100 in the number of discovered planets in the universe (of course, there are more...we just have not found them yet).
     
  12. May 19, 2003 #11

    drag

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    Greetings !

    For anyone intrested in crazy ideas I
    once imagined that Europan complex
    life forms could exist. They would
    enitialy form as organic molecules
    would stick relativly close together
    along the magnetic field lines of Jupiter
    and draw energy from the interactions
    of the field and the ocean. You would
    get very long magneticly oriented snakes.
    Another more "conventional" possibility
    is life close to the bottom of the ocean
    near the hot and gravitationaly excited
    core of the moon where the resulting
    geothermal energy could possibly nurture a
    limmited eco-system capable of supporting small
    and yet complex marine life forms.

    Live long and prosper.
     
  13. May 19, 2003 #12
    "The surest sign of alien life outside of our planet, is that none of it has ever tried to contact us" - Bill Watterson
     
    Last edited: May 20, 2003
  14. May 20, 2003 #13

    LURCH

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    When did you hear this and where? Do you have a link? I've been waiting for this quetion to be put to rest, and would love to read about the final proof.

    This article was published at Space.com just five days ago (May 15th), and the question was still open.
     
  15. May 21, 2003 #14
    I concede the possibility that I don't have the latest information, but I too would like to know where this "new news" came from. Who did it? What instruments produced these "wave beams"? How conclusive is the data? (Many properties of liquid-water and ice-water are similar.) When did it happen?

    Please prove me wrong, I'd love to know, but I can't just take your word for it. (I'm from Missouri, you gotta show me.)
     
  16. May 21, 2003 #15
    Wrong. There two forms of amino acids, left handed and right handed. Only left handed amino acids are found in life. When scientists make amino acids, only half are left handed.

    yes there are. DNA is incredibly complex. You can't just through proteins together to make it. There is a correct sequence. How do you think genetic defects happen?

    Actually, life does require amino acids, proteins, and DNA. ALL living things have them, even viruses.
     
  17. May 21, 2003 #16

    russ_watters

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    All living things that we know of anyway. You can't assume that alien life looks ANYTHING like "life as we know it."
     
  18. May 21, 2003 #17
    Originally posted by LogicalAtheist:
    There are no "right" amino acids.

    Originally posted by Psyber freek:
    Wrong. There two forms of amino acids, left handed and right handed. Only left handed amino acids are found in life. When scientists make amino acids, only half are left handed.

    No offense man, but being that I am fully educated in biology, medicine, and neuroscience, I'm not a good person to question the basis of biology with. Furthermore you missed my point completely. My point goes beyond Biology. There are two forms of amino acids out of the now 22 (or 23) discovered. Any amino acid could be inside life, not just the ones here on Earth. It's a fundamental question, you're looking to narrow. We're talking about ALIENS HERE NOT EARTHLINGS!!

    Originally posted by LogicalAtheist:
    There are no "right" proteins
    There is no "correct" DNA sequence to make cells.

    Originally posted by Psyber freek:
    yes there are. DNA is incredibly complex. You can't just through proteins together to make it. There is a correct sequence. How do you think genetic defects happen?

    See above. We're talking about aliens, and you're being earth narrow here! Life doesn't need DNA at all. And there are no correct anything for life. Way to narrow!
     
  19. May 22, 2003 #18

    For starters, sir, you did say that life as we know it doesn't depend on protein, amino acids, or DNA. (paraphrasing). So when you make a statement like that we're going to question your biology, whether or not you're "fully educated in biology, medicine, and neuroscience.)

    Secondly, if you are indeed fully educated in biology, medicine, and neuroscience than you can appreciate how complex biochemical machinery is and that it would require quite specific conditions to evolve. You seem quite sure that life doesn't need nucleic acid, but can you come up with a plausible explanation of how life could evolve without similar chemistry?
     
  20. May 22, 2003 #19

    FZ+

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    Can you make a plausible explanation ruling out the existence of life-like things without similar chemistry? Because you must show that there is absolutely no possibility of an alternative life system, not challenge show that there is such a possibility, which is the default option.
     
  21. May 23, 2003 #20
    Exactly. This is what many people don't think about.
     
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