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Why is space black?

  1. Jul 18, 2010 #1
    Why isn't it any other color? Can it be explained?
  2. jcsd
  3. Jul 18, 2010 #2


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    Staff: Mentor

    Black is the absence of color.
  4. Jul 18, 2010 #3


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    The sky is blue because the air molecules scatter light so that you see not only light coming directly from the sun and stars but also all of the scattered light that eventually gets to your eye.

    In space there is (almost) nothing to scatter light so if you are looking directly at a start you will see light from it- but no light beteen stars. No light means no color and, as Russ Watters said, no color means black.
  5. Jul 20, 2010 #4


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  6. Jul 22, 2010 #5


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    More specifically, if you're seeing black, it means no visible light is scattering towards you from the region you're seeing black.
  7. Jul 23, 2010 #6


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    Olber's paradox, not enough galaxies and stars to fill in the gaps. Olber deduced our universe cannot be both spatially and temporally infinite.
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