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Hubble Parameter

  1. Oct 22, 2007 #1
    What is the role of Cepheid stars in determining the Hubble parameter?
  2. jcsd
  3. Oct 22, 2007 #2


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    Cepheids change in brightness, the period depends on the absolute magnitude.
    By measuring the period you know how bright the star really is, you can measure how bright it appears and so find the distance.
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