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Apparent movement of stars

  1. Sep 11, 2013 #1
    Hello everybody!
    I read that because of about 4 min difference between sidereal day and solar day, at the end of a year each star has rotated 366.25 times(apparently). I looked up in software such as Starrynight, the position of for example Sirius at 1 September of 2013, 2014, 2015 and so on. I recognized that it goes up for 3 successive years and returns back to its first position at forth year. Why is it so?

  2. jcsd
  3. Sep 11, 2013 #2


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    Staff: Mentor

    Leap year?
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