The Grand Collision

Abstract

Pegasus, the Flying Horse, is the main autumn constellation, but is still on view during evenings later in the year. Its four main stars make up a square, which is easy to locate even though maps tend to make it look smaller and brighter than it really is. The upper left-hand star of the square, Alpheratz, has for some illogical reason been transferred from Pegasus to the adjacent constellation of Andromedae, and has become Alpha Andromedae instead of Delta Pegasi. Andromeda is marked by a line of stars extending from Alpheratz in the direction of Capella. Not far from the second brightish star in the line, the orange Mirach, you will find the dim blur that marks the position of the Andromeda Galaxy, M31.