re: not directly beamed

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re: not directly beamed

Arthur Smith — 12/19/2004 3:53:47 AM (archived)

"The amount of energy it would take to beam a detectable omnidirectional signal across lightyears would be staggering. "

Well, "staggering" is relative. Stars do exactly this all the time amd are a lot more than "detectable". Noting the other ongoing discussion here, all you need is devotion of a small fraction of the energy available to a level-II civilization to such a signal, to be detectable omnidirectionally. But at such an advanced technical level, beaming to candidate stars is probably a lot smarter, unless there was some other reason to do it.

The beaming and detection problems are, of course, twins - the bigger the physical aperture of your detector, the bigger your amplification and the smaller the power required at the source to be detected. Tighter beams at the source would conversely require larger and larger aperture transmitters.

The whole thread (30 posts)

Is it time to scrap SETI? Of course not! - LJK - 12/16/2004 4:47:52 PM
- SETI has a foolish perspective - Eric - 12/17/2004 12:42:09 AM
  - Since we only have a dataset of one known civilization... - Larry J - 12/17/2004 4:19:04 AM
  - re: SETI has a foolish perspective - LJK - 12/17/2004 2:05:34 AM
    - Oh, I can't resist.... - Gary - 12/17/2004 4:48:05 PM
      - Kardashev Type Civilizations - LJK - 12/17/2004 5:13:02 PM
        
        Interesting that none of them use nuclear power. - Tom Brosz - 12/18/2004 5:16:23 PM
        
        re: Interesting that none of them use nuclear power. - LJK - 12/18/2004 5:25:30 PM
        
        Kaku is a charlatan - Gary - 12/18/2004 7:00:00 AM
        
        How could he... - Adam - 12/19/2004 11:00:19 PM
        
        Believe it or not: There are physicists who are scumbags - Gary - 12/20/2004 1:40:24 AM
        
        re: Kaku is a charlatan - LJK - 12/18/2004 4:36:16 PM
        
        My model on civilization types - Gary - 12/18/2004 8:15:48 PM
        
        re: My model on civilization types - Jesse - 7/11/2005 10:05:45 AM
    - re: SETI has a foolish perspective - DWC - 12/17/2004 6:52:22 AM
- re: Is it time to scrap SETI? Of course not! - Arthur Smith - 12/16/2004 5:39:32 PM
  - How big does a radio telescope have to be? - Gary - 12/16/2004 6:59:47 PM
    - As far as detecting accidental messages - alcaray - 12/16/2004 9:12:44 PM
      - Very true - we live in a noisy RF environment - Larry J - 12/16/2004 9:56:47 PM
    - re: How big does a radio telescope have to be? - Larry J - 12/16/2004 7:24:35 PM
      - If the ETI are advanced enough, they won't need RF - LJK - 12/16/2004 10:53:43 PM
      - not directly beamed - Arthur Smith - 12/16/2004 9:07:28 PM
        
        re: not directly beamed - Larry J - 12/16/2004 9:49:56 PM
        
        re: not directly beamed - Arthur Smith - 12/19/2004 3:53:47 AM
        
        Escaping the energy limit - Nick Hoffman - 12/20/2004 3:33:22 AM
        
        Who says that ETI will use radio signals? - LJK - 12/16/2004 10:57:51 PM
        
        re: Who says that ETI will use radio signals? - Larry J - 12/17/2004 4:12:30 AM
        
        re: Who says that ETI will use radio signals? - LJK - 12/17/2004 1:05:07 PM
        
        Directional beaming & beaconing to emerging civs - p - 12/17/2004 3:08:08 PM
        
        As you might have guessed, I have thought about this topic - R.L. - 12/18/2004 8:43:26 AM

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