Why The Andromeda Galaxy Is 100 Years Old Today—And How To See It
M31, the spiral galaxy in Andromeda, with its two companion elliptical galaxies, the very small M32 … [+] below, and larger M110 above. (Photo by: Alan Dyer/VW Pics/Universal Images Group via Getty Images) VW Pics/Universal Images Group via Getty Images Andromeda, also called M31, is the closest giant neighboring galaxy at just 2.5 million light […]