In Greek mythology,

Perseus is the legendary founder of Mycenae and of the Perseid dynasty. He was, alongside Cadmus and Bellerophon, the greatest Greek hero and slayer of monsters before the days of Heracles. He was the son of Zeus and the mortal Danae, as well as the half-brother and great-grandfather of Heracles (as they were both sired by Zeus). He beheaded the Gorgon Medusa and from the cut the giant Chrysaora was born, with the golden sword and from the blood that fell into the Ocean, Pegasus, the winged horse. To avoid being chased by the Medusa sisters, he flew fast with his winged sandals or rode Pegasus. He gave the head of Medusa (Gorgoneion) to the goddess Athena, because she had helped him to kill her. Later on, he met the beautiful Andromeda chained to a rock. She was the daughter of King Cepheus and Queen Cassiopeia, who had provoked the wrath of Poseidon and sent as a punishment a sea dragon, Cetus, and demanded Andromedas sacrifice for atonement. Perseus, in love, decided to kill Cetus and take her with him. When Perseus died, the gods sent him to the stars, along with Andromeda and her parents Cepheus and Cassiopeia. Thus, were created the constellations of Perseus, Andromeda, Cassiopeia, Cepheus, Pegasus and Dragon capturing their story in the celestial dome.

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