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A star's orbit

  1. Nov 20, 2004 #1


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    When I think of a solar system I think of a star being orbited by smaller planets.But if planets orbit stars, what do stars orbit?

    Like in this picture of Andromeda:

    http://www.timelessmyths.com/classical/gallery/stars/andromeda.jpg [Broken]

    What are all those stars circling? What is that bright light in the middle?

    One more Question: If stars are what make up galaxies, what are those stars that seem to be out of the orbit and that bright object on the bottom of the picture???

    Last edited by a moderator: May 1, 2017
  2. jcsd
  3. Nov 21, 2004 #2


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    The common center of mass of the the other stars. Or in other words, the mass of stars that are closer to the center of the galaxy tha they are.
    That is the core of the Galaxy. it is just a more densely populated area of the galaxy, though many galaxies do also harbor blackholes at their centers.
    Those are other, further galaxies that the telescope picked up in the background.
    Last edited by a moderator: May 1, 2017
  4. Nov 21, 2004 #3


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    And foreground Milky Way stars. That bright object is a companion galaxy to Andromeda.

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