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Pyxis (; (ギリシア語:box)) is a small and faint constellation in the southern sky. Abbreviated from Pyxis Nautica, its name is Latin for a mariner's compass (contrasting with Circinus, which represents a draftsman's compasses). Pyxis was introduced by Nicolas Louis de Lacaille in the 18th century. The constellation is located close to those forming the old constellation of the ship Argo Navis, and in the 19th century astronomer John Herschel suggested renaming Pyxis to Malus, the mast, but the suggestion was not followed. Pyxis is completely visible from latitudes south of 53 degrees north, with its best evening-sky visibility in February and March. The plane of the Milky Way passes through Pyxis. A faint constellation, its three brightest stars—Alpha, Beta and Gamma Pyxidis—are in a rough line. At magnitude 3.68, Alpha is the constellation's brightest star. It is a blue-white star around 22,000 times as luminous as the Sun. Near Alpha is T Pyxidis, a recurrent nova that has flared up to magnitude 7 every few decades. Three star systems have planets, all discovered by doppler spectroscopy. ==History== In ancient Chinese astronomy, Alpha, Beta and Gamma Pyxidis formed part of ''Tianmiao'', a celestial temple honouring the ancestors of the emperor, along with stars from neighbouring Antlia. The French astronomer Nicolas Louis de Lacaille first described the constellation in French as ''la Boussole'' (the Marine Compass) in 1752, after he had observed and catalogued almost 10,000 southern stars during a two-year stay at the Cape of Good Hope. He devised fourteen new constellations in uncharted regions of the Southern Celestial Hemisphere not visible from Europe. All but one honoured instruments that symbolised the Age of Enlightenment. Lacaille Latinised the name to ''Pixis'' () ''Nautica'' on his 1763 chart. The Ancient Greeks identified the four main stars of Pyxis as the mast of the great ship ''Argo Navis''. German astronomer Johann Bode defined the constellation Lochium Funis, the Log and Line—a nautical device once used for measuring speed and distance travelled at sea—around Pyxis in his 1801 star atlas, but the depiction did not survive. In 1844 John Herschel attempted to resurrect the classical configuration of Argo Navis by renaming it Malus the Mast, a suggestion followed by Francis Baily, but Benjamin Gould restored Lacaille's nomenclature.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「pyxis」の詳細全文を読む スポンサード リンク
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