Andromeda Galaxy : The Andromeda galaxy is approximately 1.5 times bigger than The Milky Way, presumably has more "dark matter" than our galaxy, and is named after the princess Andromeda, of Greek mythology. Its original name was Andromeda Nebula, and is also called Messier Object 31, M31, or NGC 224. At the center of rotation is the bulge, but unlike the Milky Way's, inside of that nebula, (a compact cloud of gas and stars), are two smaller bulges, each with there respective black holes.
