Illustration of the constellation Andromeda. It is one of the original 48 constellations named by Ptolemy and remains one of the 88 contemporary constellations. It is visible in the northern sky and it is named after the princess in the legend of Perseus who was chained to a rock to be eaten by Cetus. The stars Alpheratz, Mirach and Almach among others are visible in it as well as M31 the spiral or Andromeda Galaxy.