The Myth of Cassiopeia
According
to a Greek legend, the sea god Poseidon placed the figure of Cassiopeia among
the stars. It is said that Cassiopeia has a ridiculous upside-down position
to punish her for having been pretentious. Cassiopeia was very proud of her
beauty. She claimed that she and her daughter Andromeda were more beautiful
than the sea-nymphs, the Nereids.
The nymphs complained to the sea god Poseidon, who threatened to send a sea
monster and flood to destroy Cassiopeia's land. In despair, the king Cepheus
consulted an oracle to prevent the destruction of his reign. The oracle predicted
that only the sacrifice of Andromeda to the monster could appease the wrath
of Poseidon.
The
king chained Andromeda to a sea cliff. Fortunately, at this same moment, Perseus,
the nephew of the king of Argos, was traveling along the coast. Perseus noticed
the beautiful woman and fell in love with her. Learning of Andromeda's story,
he offered to rescue her if her parents agreed to let him marry their daughter.
With the help of some magical sandals that allowed Perseus to fly, and a magical
sword given to him by the god Hermes, Perseus killed the monster and married
Andromeda.
Cassiopeia,
abbreviated Cas, in astronomy, a constellation of the northern sky, easily
recognized by a group of five bright stars forming a slightly irregular W.
It lies at one hour right ascension (the coordinate of the celestial sphere
analogous to longitude on the Earth) and 60º north declination (angular distance
north of the celestial equator). Tycho's nova, one of the few recorded supernovae
in the Galaxy, appeared in Cassiopeia in 1572.