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Cassiopeia,in astronomy, prominent northern constellationconstellation,
in common usage, group of stars that appear to form a configuration in the sky; properly speaking, a constellation is a definite region of the sky in which the configuration of stars is contained.
..... Click the link for more information. located almost directly opposite the Big Dipper across the north celestial pole. Five bright stars in the constellation form a rough W (or M) in the sky. Some see in this formation the shape of a chair known as Cassiopeia's Chair. Tycho's Star, a supernovasupernova,
a massive star in the latter stages of stellar evolution that suddenly contracts and then explodes, increasing its energy output as much as a billionfold. Supernovas are the principal distributors of heavy elements throughout the universe; all elements heavier than
..... Click the link for more information. , appeared in the constellation in 1572 and disappeared in 1574. In this constellation is located Cassiopeia A, a discrete radio source emitting 21-cm radiation with great intensity. Cassiopeia reaches its highest point in the evening sky in November, but because of its location near the pole it is visible throughout the year to most northern observers.
Cassiopeia(kăs'ēəpē`ə), in Greek mythology: see AndromedaAndromeda
, in Greek mythology, princess of Ethiopia, daughter of King Cepheus, king of Ethiopia, and Cassiopeia. According to most legends Cassiopeia angered Poseidon by saying that Andromeda (or possibly Cassiopeia herself) was more beautiful than the nereids.
..... Click the link for more information. .
Cassiopeia(kass-ee-ŏ-pee -ă) A conspicuous constellation in the northern hemisphere, lying partly in the Milky Way. The five brightest stars form a W-shape, which includes Schedar (α), the blue-white visual binary Cih (γ), which is an irregular variable and an X-ray source, and the cream-colored Caph (β), all of 2nd magnitude. Eta, close to Schedar, is a 3rd-magnitude binary star. The area contains some fine open clusters (M52 [NGC 7654], M103 [NGC 581], NGC 457 and NGC 663) and globular clusters and the remnants of two recent supernovae – Tycho's star and the radio source Cassiopeia A. Abbrev.: Cas; genitive form: Cassiopeiae; approx. position: RA 1h, dec +60°; area: 598 sq deg.
a constellation of the northern sky. Its brightest stars ε, δ, γ, α, and β, which form a figure W, have brightnesses of 3.4, 2.7, 2.4, 2.2, and 2.3 visual stellar magnitudes, respectively. In 1572 a supernova flared up in the constellation. The most powerful known source of radio emission originates from the constellation, which is located in the Milky Way. The best conditions for observing it are from September to November. It is visible the year round everywhere in the USSR. It is named for Cassiopeia, in ancient Greek mythology the wife of the Ethiopian king Cepheus and the mother of Andromeda.