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How far can your cat see into the universe?

  1. Sep 8, 2009 #1
    http://en.wikipedia.org/wiki/List_of_galaxies#List_of_naked-eye_galaxies". M101 is 27 million light years away.

    I've read that the eye of a cat can collect about 20 times more light than the eye of a human. Then, given the brightness of the dimmest galaxies that have been seen by humans, that seems to imply that http://www.atlasoftheuniverse.com/galax200.html" [Broken] should be visible to a cat.
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Sep 8, 2009 #2
    does the fact (presumably) that a cat's eye can collect more light than an eye of a man really mean that a can can see further?
    im not the smartest person and pretty new to this forum, but to me it seems that it only makes the cat see wider.
    plus, i think it also depends alot on the ciliary muscles of the eye of cats.
  4. Sep 12, 2009 #3
    yeah good point, more light = better resolution, not magnification. Basic microscope concepts.
  5. Sep 12, 2009 #4
    Cat's eyes have a "mirror" behind the retina to reflect light back into the light sensor cells. See
    Our neighbor's cat maybe could see galaxies, but she didn't see the coyote that got her last night. She wasn't the smartest cat on the block.
    Last edited by a moderator: Apr 24, 2017
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