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Parallax questions

  1. Jan 24, 2007 #1
    Can somebody please confirm that my answers are right?
    1. At what time on earth did the light start from a galaxy 2 billion light years away?
    My answer was 2 X 10^9 years. This problem seemed too easy to be true.

    2. How far is the nearest star in kilometers (about 1.3 par sec away)?
    My answer: 3.77 X 10^12 km

    Thanks for the help!
     
  2. jcsd
  3. Jan 25, 2007 #2
    Welcome to PF, pianoparadaise.

    In the first question, if it's light that we're seeing "now," then you're answer is right.

    As for the second, if it's the nearest star to the solar system, then the answer is off by a factor of 10 or so.
     
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