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Cellular Phone Spectra and Earth's SETI Invisibility

astrobio writes: "How long will the Earth's technology be detectable to other worlds? From an article today by the Chairman of the SETI Institute: 'Not long, with shared transmission spectra. To transmit ever-increasing amounts of information, portions of the spectrum must be shared. This is only possible if signal strengths are reduced so that transmissions on the same frequency do not interfere with one another. The textbook example of this paradigm is the cellular phone system. This signal reduction means we are well on our way to becoming invisible.'"

5 of 51 comments (clear)

  1. This may be a Good Thing by rpjs · · Score: 3, Insightful

    Because do we really want to let the universe know we're here? Contact with a more advanced civilisation might have unfortunate repercussions for us - look at the impact contact with the West had on so many indigenous cultures during the ages of exploration and imperialism.

    And that's just assuming the ETs are benevolent and simply can't help having the effect on us that we have on a newly contacted tribe in the Amazon. What if the ETs are paranoid about competitor intelligences arising and have a policy of wiping out any new civilisation that pops its head up over the electro-magnetic parapet? That's one of the more pessimistic explanations for the Fermi Paradox.

    1. Re:This may be a Good Thing by Rhombus · · Score: 2, Insightful
      Good point....look at StarFleet...they have a specific rule against this sort of thing, and it gets broken about twice an episode. :P

      Seriously, though, if we were to discover an alien race that was technologically inferior to us, I entertain no illusions as to how our species would corrupt and exploit them. Why do we assume that alien races technologically superior to us would be equally superior ethically?

    2. Re:This may be a Good Thing by whovian · · Score: 3, Insightful

      On the other hand, what if a civilization gets the idea of "aliens" for the first time by discovering patterned interstellar radio signals? It's an involuntary violation of the Prime Directive on our part. In the big scheme of the universe (whatever that may be) I don't think this is so serious.

      On the other hand, that civiliation too would probably get sued under DMCA :P

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  2. Not True by Perdo · · Score: 3, Insightful

    I thought of this years ago. Then realized I was wrong. How much power does your local AM radio station put out? 50,000 watts. Will the ammount of power required to broadcast to three states ever drop? Nope. How many 50,000 watt radio stations are there in the US alone? Over 8000.

    Will XM sattelite radio change that? Has linux been able to break Microsoft's monopoly?

    --

    If voting were effective, it would be illegal by now.

  3. Re:A limited form of invisibility by dzym · · Score: 3, Insightful
    There is no reason expect that oxygen is the basis for all life in the universe. The scientific community has become increasingly aware of small bacteria-sized creatures currently termed archaea. These creatures do not depend on photosynthesis for their nutrition but instead rely on varying and diverse elements (including some of the "heavy" ones) and presumably also do not require the existence of massive amounts of oxygen to survive/thrive.

    Bottom line: don't assume that just because humans require oxygen to survive, that any other alien species must also, and that they would necessarily also search for oxygenated worlds.