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Extraterrestrial life?

Do you believe in extraterrestrial life?

Poll closed Jun 27, 2007.
  1. yes...no doubt about it

    14 vote(s)
    51.9%
  2. of course not

    0 vote(s)
    0.0%
  3. i don't know...

    4 vote(s)
    14.8%
  4. it is not an important question

    1 vote(s)
    3.7%
  5. yes..but i'm not sure

    8 vote(s)
    29.6%
  1. Jun 17, 2007 #1
    i think this is a complex question...what you guys think about this?
     
  2. jcsd
  3. Jun 17, 2007 #2

    marcus

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    I think it is a waste of time to get bogged down in speculation about extraterrestrial life.

    What is more interesting, in that department, is the discovery of earth-like planets and the development of methods to extend terrestrial life to them.
     
  4. Jun 17, 2007 #3
    how long do you think that it will take to detect an earthlike planet?
     
    Last edited by a moderator: Jun 18, 2007
  5. Jun 17, 2007 #4

    marcus

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    as a rough estimate I would expect there to be on the order of 10 good candidates, forming a short list to be studied in more detail, in on the order of 10 years.

    a lot of orbital and ground-based astronomical instruments will be being used to find out more about conditions on them, by that time.
     
  6. Jun 17, 2007 #5
    yeah...da number of extra-solar planets' increasin as da number of telluric or somewhat teluriclike planets aswell...maybe in da next decade
     
    Last edited by a moderator: Jun 18, 2007
  7. Jun 17, 2007 #6

    cristo

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    I like this idea, however am not sure what the chances are of finding a planet suitable of sustaining life within travelling distance from the earth.

    Firstly, I presume you mean "telluric" (earth-like). Secondly, it should be noted that when marcus used the term "in the order of ten years" he means within zero and one hundred years time, not in the next decade.
     
  8. Jun 18, 2007 #7
    telluric doesn't mean earth-like...it comes from latin and it means rock-like...and when i said "in the next decade" i was refering to telluric planets not planets with life...aight?
     
  9. Jun 18, 2007 #8

    cristo

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    Erm...
    I presumed that, since we are discussing extraterrestrial life, you would be using the first definition.. :rolleyes:
    Now correct me if I'm reading marcus' post incorrectly, but I'm sure he is talking about candidates to be earth-like planets also.

    Aight?
     
  10. Jun 18, 2007 #9
    erm? lol...u look like george bush...but it's ok...the main subject here is ET life...let's talk about it
     
  11. Jun 18, 2007 #10

    wolram

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    The only fact i know is that we have not detected extraterrestrial life.

    Even if we did find life on a par with us at say, 10lys, 20llys, 50lys distant
    what would the advantage be to us?
     
  12. Jun 18, 2007 #11
    We don't have evidence of ET(I). But I believe that it should exist...it would be really stupid to have a whole universe which just a bunch of nitwits.
     
  13. Jun 18, 2007 #12

    DaveC426913

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    It would put to rest once and for all the question of whether we're unique. In this case, 1+1= way more than 2.
     
  14. Jun 18, 2007 #13
    Just playing the odds, given the number of systems out there, there really must be life all over the place. But also playing the odds, given the number of species on our planet that can do science/math, it is probably not so likely that "intelligent" life is very common.
     
  15. Jun 19, 2007 #14
    The mere existence of a UFO shatters the well protected dogmas of modern science. The extra-solar origins of UFO's suggest faster than light travel. Their right angle turns at extreme velocities, non-conventional propultion systems, and other oddities defy the laws of newtonian and einsteinian physics.
    This is why no amount of evidence, even if it is throughout mankinds history, will convince the bulk of the scientifc community of their existence.
     
  16. Jun 19, 2007 #15

    russ_watters

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    That may be more of a topic for the S&D forum, but the quality of evidence currently available to show that UFOs are actually extraterrestrial spacecraft is very low. A large quantity of low-quality evidence is no substitute for a small quantity of high quality evidence.

    Btw, Ivan - here's an example of an alien spacecraft proponent using the term UFO to mean "alien spacecraft".
     
  17. Jun 19, 2007 #16
    only the most conservative scientists...there are new scientific streams which tolerate the possibility of such travels
     
  18. Jun 19, 2007 #17

    cristo

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    Why would alien spacecraft necessarily have to travel faster than the speed of light?
     
  19. Jun 19, 2007 #18

    Ivan Seeking

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    Obviously if we knew a craft to be of extraterrestrial origin it wouldn't be a UFO, which is why we call UFOs, UFOs - as in "unidentified". Once identified, such as in the cases of ball lightning and earth lights, they are referred to as such and not as UFOs.

    I believe that virtually any interpreation of Drake's equation, when applied to the entire universe, yields a probability for life out there of [almost exactly] 1.
    http://www.amazon.co.uk/Probability-One-Amir-D-Aczel/dp/0316648299

    From a statistical pov, we are certainly not alone.

    late edit for clarity
     
    Last edited: Jun 19, 2007
  20. Jun 19, 2007 #19
    Life....yes, but "intelligent" life? I think the odds are still against it. Think of all the billions upon billions of species on our planet. How many of those are capable of space travel? Just one.

    Especially if our universe is really as young as it is supposed to be. Considering the amount of time it must take to build the elements that make up life and the amount of time for that life to evolve into something like us, we may very well be the first "intelligent" life in the universe. :uhh:
     
  21. Jun 19, 2007 #20

    Ivan Seeking

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    http://pubs.wri.org/pubs_content_text.cfm?ContentID=535 [Broken]

    And many species differ very little so this is somewhat misleading. But again, only the most conservative interpretation of Drakes equation leaves anything but a very large number when multiplied by the number of galaxies in the universe. [Earlier I was stating it as a probability, which was somewhat confusing.]

    How many species might have become intelligent but went extinct due to random events? For all we know, with time, intelligence as you define it may be inevitable anywhere that life exists.
     
    Last edited by a moderator: May 2, 2017
  22. Jun 19, 2007 #21

    Ivan Seeking

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    Also,
    http://www.newscientist.com/channel...85.400-neanderthals-bid-for-human-status.html

    And lets not forget what appears to be another intelligent species in our world's history, homo floresiensis, who apparently had fire and used tools and weapons.
    http://news.nationalgeographic.com/news/2004/10/1027_041027_homo_floresiensis.html,
     
    Last edited by a moderator: Apr 22, 2017
  23. Jun 20, 2007 #22

    Chronos

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    Neanderthal practiced ritual burial, built fires, used tools, and created artistic works. I'm curious to whom Hopkinson attributed the 'incapable of innovation' assertion. There is at least a fair chance homo erectus used fire:
    http://anthro.palomar.edu/homo/homo_3.htm
     
  24. Jun 20, 2007 #23
    I think that estimate is very conservative since there could be as many as 50 million insect species alone while recognizing my estimate was grossly high. But you also make a good point about diversity.

    I guess all life needs to do is get to the point where they can do some "higher" communication and start dealing with mathematical concepts and the rest comes quite swiftly (thousands of years). Given the number of galaxies, I guess I can see the probability being high, but constrained to just our galaxy (since inter-galaxy travel seems impossible), I still bet it's pretty low chances that aliens are out there flying around in spaceships.
     
    Last edited by a moderator: May 2, 2017
  25. Jun 20, 2007 #24

    russ_watters

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    That interpretation assumes that the universe is spatially infinite. Regardless of whether or not it is true, it isn't a terribly useful assumption. Besides potentially yielding a [itex] (1/ \infty) * \infty [/itex] situation, it doesn't provide us with an answer that has any meaning. The Drake equation was designed for our galaxy only and it is speculative enough as it is! It may be a catchy title for a book, but it doesn't have any meaning beyond that. And, in fact, the book wasn't written for that purpose anyway, but just uses it as teaser and a jumping-off point to discuss the actual purpose of the drake equation: We already know that the probability of life existing in the universe is exactly 1. The point of the Drake equation is to guestimate how much life there is in the universe.

    Btw - I answered with the last poll option.
     
    Last edited: Jun 20, 2007
  26. Jun 20, 2007 #25

    Ivan Seeking

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    Just out of curiosity, have you read the book?

    The point of the drake equation is to estimate how much life might be in the galaxy, not the universe. So when we extrapolate this to the entire universe, any Drake result larger than zero yields a very large number.

    The poll asks if there is any extraterrestrial life, so the "probability 1" seemed appropriate to mention. He uses the Drake equation in his reasoning.
     
    Last edited: Jun 20, 2007
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