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How would you actually know it's light took 2 million years to reach us? After taking 2 million years, and using the speed of light, that galaxy would be aprox. 117559095133820000000 miles away. Wow...




Almost right. It's center is even 2.5 million light years away, or about 1.5x10^19 miles.

http://en.wikipedia.org/wiki/Andromeda_Galaxy