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Homework Help: Cosmolgy- Density of the Universe

  1. Sep 11, 2006 #1


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    Assume the universe has an average galaxy density of p=0.9 Mpc^-3. Each galaxy has a diameter of 30 kpc. How far would you see on average in any direction before your line of sight would hit a galaxy? Assume a Eucledian spcae and infinitely large and infinitely old universe.

    Help get me started.

    My guess is the answer is that no matter where you look you'll see a galaxy under these conditions.
  2. jcsd
  3. Sep 11, 2006 #2

    Andrew Mason

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    What units are are kpc and mpc?

  4. Sep 11, 2006 #3


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    Kiloparsec and Megaparsec
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