How to spot the Perseus constellation 🌌🌠 Perseus is one of the biggest constellations in the night sky. Its namesake was said to have saved Andromeda from being sacrificed to the sea monster Cetus, both of which lend their names to other constellations. To find Perseus, we can use the neighbouring constellation of Cassiopeia (mother of Andromeda in mythology). It has five bright stars that make a W in the northern hemisphere, or M in the southern. The shallower of these two Vs will be our guid