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B When photons from distant stars [etc] are received, what about the rest of the EM spectrum?

  1. Nov 29, 2018 #1
    When photons from distant stars [etc] are received why does the rest of the electromagnetic spectrum not reach us.
  2. jcsd
  3. Nov 29, 2018 #2


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    What makes you think it doesn't?
  4. Nov 29, 2018 #3


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  5. Nov 29, 2018 #4
    In comparison to radio waves (in general) it's usually the opposite because interstellar and intergalactic materials (powders, etc) are transparent to radio waves but not always to visible light.

  6. Dec 5, 2018 #5
    Am I missing something, but aren't photons the carrier of all electromagnetic radiation regardless of frequency? So they're all being emitted, some are absorbed or transduced along the way, but a lot reaches us. We view the cosmos in many frequencies right here on Earth.
  7. Dec 5, 2018 #6


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    No they are not.
    EM emissions is mostly frequency specific .... eg. monochromatic light .... a red laser ... is very frequency specific radio, TV broadcasts ....
    else why would they bother to give you a specific frequency to tune to for your favourite FM radio station eg. 101.7 MHz
    Some sources are broad band, but even then not necessarily/not likely to be right across the whole spectrum

    ohhh and photons are quantum packets of energy (at a specific frequency) :smile:
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