Cassiopeia

Cassiopeia is a constellation in the northern sky and a figure from Greek mythology. In myth, Cassiopeia was the queen of Aethiopia, wife of Cepheus and mother of Andromeda. She boasted that she and her daughter were more beautiful than the Nereids, provoking the wrath of the gods. As punishment she was placed in the heavens on a throne; the throne is drawn such that she spends half the time seated upright and half the time inverted, a reminder of vanity.

As a modern astronomical constellation, Cassiopeia is easily recognized by its distinctive five bright stars that form a W (or M) shape. The brightest stars are known by traditional names such as Schedar (Alpha Cassiopeiae) and Caph (Beta Cassiopeiae). The pattern is a prominent feature of the northern sky and serves as a navigational reference in that region.

Within Cassiopeia lie several notable deep-sky objects, including Cassiopeia A, a young supernova remnant visible in radio and X-ray wavelengths, and NGC 281, the Pacman Nebula, an H II region undergoing star formation. The constellation also contains star clusters and other emission nebulae.

Cassiopeia is a circumpolar constellation for much of the Northern Hemisphere, visible year-round from many latitudes, with best viewing in autumn evenings. Its name and shape are used in astronomy and culture as a symbol of the northern sky.