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Calculating absolute magnitude

  1. May 10, 2009 #1
    Sirius A has an apperant magnitude of -1.5, and his distance from us is 2.6 pc. the sun has an apperent magnitude of -26.8 and a distance of 1 AU.
    what is Sirius's absolute magnitude?
    how meny times is Sirius brighter then the sun?

    this is the equation i'm supposed to use, its the one they gave me.
    i think it is much more oppropriate to use:
    and then just dividing to find how much brighter he is.

    so, what unit does the distance "d" needs to be in? and how do i calculate the answers with the first equation?
    and what is flux? i couldnt get a clear explanation anywhere.
  2. jcsd
  3. May 11, 2009 #2
    can someone please help me?
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