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Size of horsehead nebula

  1. May 16, 2009 #1
    Hi,

    I was looking at information about the Horsehead nebula on wikipedia
    http://en.wikipedia.org/wiki/Horsehead_nebula

    and it says that its apparent dimensions are 8x6 arcmins.

    I'm not sure how to find the actual dimensions, say in light-years. Here's how I believe it should be, but I'm sure I'm wrong.

    According to wikipedia, the nebula is 1500 ly away. 1 arcmin = 1/60 degrees. So the dimensions should be:

    1500*tan(8/60) by 1500*tan(6/60), which is 3.5 ly by 2.6 ly.

    Have I got it right, or have I missed something obvious.

    Thanks,
    Maria
     
  2. jcsd
  3. May 17, 2009 #2

    Nabeshin

    User Avatar
    Science Advisor

    Confirmed.
     
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