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Stargazing Our picture of the universe

  1. Apr 14, 2016 #1
    I'm not sure if this has already been discussed, but does our picture of the universe become less and less accurate the farther we look? By farther I mean light years away, when we concentrate our telescopes to a certain area light years away, could we be looking at a star that we aren't seeing but is there or vice versa?
  2. jcsd
  3. Apr 14, 2016 #2


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    It becomes less specific and less precise but it does not become less accurate unless the Cosmological Principle is wrong, and how likely is that?
  4. Apr 14, 2016 #3
    It depends on the scale you are talking about. If, for example, you are referring to the location of a single star, then the answer is yes. The closer the star is to us, the more accurately we can determine its distance. At a distance of about one million parsecs (3,261,560 light years) we can no longer identify individual stars (unless they are going supernova). Therefore, the further an object is away from us, the less accurate we can be about its distance.

    At distances beyond one million parsecs we no longer focus on individual stars, but rather look at individual galaxies and approximate their distance by either using Type Ia supernova or red shift. The former being more accurate than the latter.
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