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Could we even theoretically detect readio signals from extraterrestrial intelligence?

  1. Jun 17, 2010 #1
    I mean, several light years from here, is it possible to distinguish between the signals coming from Earth and the massive amount of electromagnetic radiation emitted by our Sun? From a great distance, every solar system must appear dot-like.

    Is it possible that civilizations are actually trying to communicate but are unable to do so because their signals are overpowered by their respective suns'?
     
  2. jcsd
  3. Jun 17, 2010 #2
    Re: Could we even theoretically detect readio signals from extraterrestrial intellige

    I think a civilization advanced enough could create a unique, powerful signal to get through the stellar noise. But I'm no expert...

    I'm not sure the 'beacon' approach to signaling is what an advance civilization would do. They'd probably have directed signals at systems and/or planets with probable life.
     
  4. Jun 17, 2010 #3

    Nabeshin

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    Re: Could we even theoretically detect readio signals from extraterrestrial intellige

    I'm pretty sure we (humanity) could create a signal that we (humanity) could detect at a distance of some thousands of light years. See, for example, the arecibo message.
     
  5. Jun 18, 2010 #4

    Chronos

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    Re: Could we even theoretically detect readio signals from extraterrestrial intellige

    I'm less optimistic, nabeshin. Ciphering an intelligient [even terrawatt] signal from background noise in the universe is hugely difficult after a a few tens of light years - and that assumes you know the signal type and frequency for which to search. I'm a big fan of SETI and an optimist, but, it is not an easy task, IMO.
     
  6. Jun 19, 2010 #5
    Re: Could we even theoretically detect readio signals from extraterrestrial intellige

    Hmm a filosofical point of view about SETI.
    We would call intelligent a creature that cares, comprehends and tries to reach out for the outer space (without built in curiosity one can never grow intelligent)
    now reagrding that if we will ever meet any form of life it is very slim chance they will be exactly at the same developement stage like us. more likely it will be somewhere between bilion year ahead of us or billion year behind us.
    since billion year behind us is called unintelligent, so

    if we will ever find any intelligent creature it will be inbetween like us to billion year ahead of us.

    now it is widly believed that humans advance exponencially, so after even few hundred years the technological progress is beyond imagination (harnessing, directing gravity for e.g.)

    now statistically if there is an intelligent life they most likely are WAY WAY WAY ahead of us and thus the means of communication are also ahead of us,
    they can borth receive week signals, and transmit superpowerfull signals
    they should be detectable easily
    the absence of this means - they dont want to be detected or they dont exist. both are frightening.

    sorry for being filosofical
     
  7. Jun 19, 2010 #6
    Re: Could we even theoretically detect readio signals from extraterrestrial intellige

    Likely or not, I think we can all agree that it's possible. What if the signal sent used a massive antenna array planet-wide, with our full energy production? WE might not do that, but perhaps a doomed, or moving civilization might?
     
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