... M31: The Andromeda Galaxy . ... What is the nearest major galaxy to our own Milky Way Galaxy? Andromeda. In fact, our Galaxy is thought to look much like Andromeda. ... The diffuse light from Andromeda is caused by the hundreds of billions of stars that compose it. ... Is this coat hanger a star cluster or an asterism? ... Many of the brightest blue images are of a single, unusual, beaded, blue, ring-like galaxy which just happens to line-up behind a giant cluster of galaxies. ...