Pegasus can be located by searching for the faint but large "Great Square of Pegasus". The constellation of Pegasus is used by astronomers to locate the Andromeda Galaxy – our closest neighbouring galaxy and the source of the oldest and faintest light visible to the naked eye.
In Greek mythology Pegasus was the son of Poseidon and Medusa. Poseidon the god of the sea and horses, seduced Medusa, a mortal, in the Temple of Athena. As a punishment Athena covered Medusa's body in scales and turned her hair into snakes! Any mortal who looked at Medusa turned to stone. The hero Perseus slew Medusa and Pegasus sprang from her blood up into the heavens where the winged horse carried Zeus' lightning bolts.