How Big is the Andromeda Galaxy?

If you have ever seen the Andromeda Galaxy, M31, in the sky or through a telescope, you’ll find it’s reminiscent of a small blurry, fuzzy patch, almost like a cloud. The cloudy look is similar to looking at the hazy white glow of the milky way’s concentrated disk. But that cloudy view is not all of M31.  The galaxy is so far away, around 2.5 Million light years, that you’re only seeing the concentrated light from its central bulge.  You’re actually missing a large portion of the galaxy because its just too dim for your eyes to see. If you can take a...