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From Andromeda

  1. Jan 28, 2012 #1
    If an observer on the Andromeda galaxy looked back at us, how would the Milky Way galaxy look to him? Edge-on, spiral face on, or in between?
  2. jcsd
  3. Jan 28, 2012 #2


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    It depends on whether the constellation Andromeda is in the Milkyway band of stars. As I recall, it is more or less. Therefore he would see us edge on (if that is true).

    Yes. Look!

    This map shows the band of the Milkyway, and it also shows a dot where the Andr. galaxy is. It is not right exactly in the band, but rather close.

    It is within 15 degrees of the center of the band. 15 degrees is a fairly small angle. So he would not see us exactly edge on, but with a slight tilt of 15 degrees.
    Last edited: Jan 28, 2012
  4. Jan 28, 2012 #3


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    Andromeda (m31) is about 20 degrees below the Galactic plane. So, I assume that, looking back along that line of sight , you'd see the MW as somewhere between edge-on and face on, but closer to edge on.
  5. Jan 28, 2012 #4
    A bit like we see Andromeda then? Thanks!
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