Its 14th-magnitude companion completes an orbit around it in about 27 days.Īt the midpoint of the W is Gamma Cassiopeiae, sometimes called Cih or Tsih, Chinese for “whip.” It is a blue-white star whose magnitude varies unpredictably from 3.0 to 1.6, perhaps as a result of its very high rate of rotation. Caph is a rare type of aging double star. It is 45 light-years away from Earth and 30 degrees from Polaris, the north star. The name Caph (Beta Cassiopeiae) comes from the Arabic meaning “palm.” Caph is a white, pulsating variable star whose magnitude brightens from 2.31 to 2.25 over 2.5 hours. Schedar has three faint optical companions that do not form a true multiple star group. Although variations in the brightness of Schedar were observed in the 19th century by John Herschel and Friedrich Argelander, none have been seen in recent years. Schedar is a second-magnitude yellow giant about 110 light-years away from Earth. The Arabic meaning of the name Schedar (Alpha Cassiopeiae) is “breast,” which it marks in the constellation. The stars that form the easily visible W of Cassiopeia include Schedar, Caph, Cih (or Tsih), Ruchbah, and Segin. Cassiopeia is sometimes referred to as “the lady in the chair.” This explains the constellation’s apparent change of position as it circles the sky sometimes it is shaped like the letter W, and sometimes it is upside-down, appearing like an M. When Cassiopeia was placed in the heavens after her death, in order to humble her she was positioned so that she would have to spend half of her time upside down and bound to a chair. He chained Andromeda to a rock, but she was saved by the hero Perseus. When King Cepheus consulted an oracle for help, he was told that only by sacrificing the beautiful Andromeda could he appease the gods and avert destruction of the kingdom. To punish her for her vanity the Nereids had Poseidon, god of the seas, send a sea monster to plague the shores of the kingdom. She offended the Nereids, or sea nymphs, when she boasted that she was more beautiful than they.
Cassiopeia was married to Cepheus, king of Ethiopia.
In Greek mythology, Cassiopeia was a vain Ethiopian queen who put the life of her daughter, Andromeda, in danger. Two of its galaxies are companions of the famous Andromeda galaxy. Cassiopeia is known for its wealth of multiple stars and open star clusters. The five important stars of the constellation form a distinctive, irregular W in the sky. Cassiopeia is one of 48 constellations cataloged by the 2nd-century Greek astronomer Ptolemy. Cassiopeia is bordered on the north and west by Cepheus, on the south by Andromeda, and on the southeast by Perseus-constellations to which it is related through mythology and star lore. Its northern end terminates only 12 degrees from the north celestial pole. latitude and reaches its height in the sky at 10:00 pm on November 10, making it a fall–winter constellation in the Northern Hemisphere. It is visible year-round to observers north of 40° N. In astronomy Cassiopeia is a north circumpolar constellation. NASA/JPL/California Institute of Technology
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