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Theoretical Question about Milky Way

  1. May 7, 2010 #1
    This may be a stupid question, but it just popped up in my mind a few minutes ago. Considering we are able to "look back in time" so to speak, because light takes so long to get here, is it possible for us to look in the night sky and see light that came from the Milky Way?

    Considering the universe is expanding, and has been expanding ever since it began, wouldn't it be possible to say, look at the cosmic microwave background and actually see our galaxy as it was a few billion years ago?
  2. jcsd
  3. May 7, 2010 #2


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    It doesn't work like that.
    We are in the middle of the galaxy, about 30,000lyr from the center - so when we look at the center we see light that left there 30,000 years ago.
    The most distant bits of the milky way are about 100,000lyr away
    The universe expansion doesn't do anything on the scale of a galaxy.
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