The Great Andromeda Galaxy. The Great Andromeda Galaxy (M31; NGC 224) is located 2.2 million light years from Earth in the constellation Andromeda. At 200 light years across it is the largest galaxy in the "local group" - the cluster of around 25 galaxies that includes our own, the Milky Way. Like the Milky Way, Andromeda is a spiral galaxy with a dense central bulge packed with millions of stars. This photograph also shows two small companion galaxies near Andromeda: the irregular galaxy NGC 205 (right) and the elliptical galaxy NGC 221 (the small star-like object just below Andromeda's center).