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Light from flashlight

  1. Nov 27, 2013 #1
    Does the light ,if I turn on the ordinary flashlight source somewhere here on Earth,go into the space.
    And Does if it become completely mixed with all other electromagnetic radiation there would be some fraction of all that radiation that is still "my light" and would be (even with odds 1/∞) there some miserable chance to be detected as a "some specific signature" ? :)
  2. jcsd
  3. Nov 27, 2013 #2


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    Yes, the light can go into space. But it won't be detected as a specific signal, as it's just plain old white light.
  4. Nov 27, 2013 #3


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    Any instrument that receives your particular light beam will have to cope with all the other signals from that general direction (there is a limit to the resolution of any such interment) plus the naturally occurring 'noise' in the receiver. Detecting your signal will depend upon the signal to (noise plus interference) ratio at the receiver - as in all forms of communication.
    You could improve on the reception by flashing the lamp at a pre-arranged rate and then looking for that oscillation frequency at the receiver. This is a well known experimentaltechnique (synchronous detection) which improves detection of low level signals.
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