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Antlia (; from Ancient Greek ''ἀντλία'') is a constellation in the southern sky. Its name means "pump" and it specifically represents an air pump. The constellation was created in the 18th century from an undesignated region of sky, so the stars comprising Antlia are faint. The brightest star is Alpha Antliae is an orange giant that is a suspected variable star, ranging between apparent magnitudes 4.22 and 4.29. NGC 2997, a spiral galaxy, and the Antlia Dwarf Galaxy lie within Antlia's borders. ==History== The French astronomer Nicolas Louis de Lacaille first described the constellation in French as ''la Machine Pneumatique'' (the Pneumatic Pump) in 1751–52, commemorating the air pump invented by the French physicist Denis Papin. He had observed and catalogued almost 10,000 southern stars during a two-year stay at the Cape of Good Hope, devising 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 ''Antlia pneumatica'' on his 1763 chart. John Herschel proposed shrinking the name to one word, which was universally taken up. Though Antlia was technically visible to ancient Greek astronomers, its stars were too faint to have been included in any constellations.〔 Because of this, its main stars have no particular pattern and it is devoid of bright deep-sky objects.〔 Lacaille and Johann Bode each depicted Antlia differently, as either the single-cylinder vacuum pump used in Papin's initial experiments, or the more advanced double-cylinder version.〔 The International Astronomical Union subsequently adopted it as one of the 88 modern constellations. There is no mythology attached to Antlia as Lacaille discontinued the tradition of giving names from mythology to constellations and instead chose names mostly from scientific instruments.〔 According to some, the most prominent stars that now comprise Antlia were once included within the ancient constellation Argo Navis, the Ship of the Argonauts, which due to its immense size was split into several smaller constellations by Lacaille in 1763.〔Peter Birren (2002) Objects in the Heavens, pp. 9, 45 (ISBN 155369662X).〕〔Thomas William Webb (Dover Publications 1962) Celestial objects for common telescopes, Volume 2, p. 36.〕 However, given the faintness and obscurity of its stars, most authorities do not believe that the ancient Greeks included Antlia as part of their classical depiction of Argo Navis.〔Ian Ridpath (2002) Stars and Planets, pp, 65, 122. (ISBN 0-7894-8988-0)〕 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「Antlia」の詳細全文を読む スポンサード リンク
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