Cassiopeia

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Cassiopeia (astronomy), northern constellation, near the celestial pole. It is distinguished by a group of five stars, of second to fourth magnitude, in the form of a rough letter W. The brightest supernova on record appeared in the constellation in 1572 and was observed by the Danish astronomer Tycho Brahe. Brighter than the planet Venus, for about 16 months Cassiopeia was visible to the naked eye even at noon. It is named for the mythological Ethiopian queen Cassiopeia, the mother of Andromeda.

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