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Size of horsehead nebula

by Maria76
Tags: horsehead, nebula, size
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May16-09, 11:18 PM
P: 14

I was looking at information about the Horsehead nebula on wikipedia

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.

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May17-09, 02:12 AM
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P: 2,193
Quote Quote by Maria76 View Post
1500*tan(8/60) by 1500*tan(6/60), which is 3.5 ly by 2.6 ly.

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