Pyxis

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Pyxis is a small and faint constellation in the southern sky. Its name is Latin for a mariner's compass (it should not be confused with Circinus, which represents a draftsman's compasses). Pyxis is completely visible from latitudes south of 53 degrees north, with its best evening-sky visibility in January through March. The brightest star is Alpha Pyxidis at magnitude 3.68.Pyxis was introduced by Nicolas Louis de Lacaille in the 18th century; he called it Pyxis Nautica, but the name was shortened. The constellation is located close to those forming the old constellation of Argo Navis (the ship Argo), and in the 19th century astronomer John Herschel suggested renaming Pyxis to 'Malus, the mast', but the suggestion was not followed.

Pyxis

Pyxis is a small constellation bordered by Hydra to the north, Puppis to the west, Vela to the south, and Antlia to the east. The three-letter abbreviation for the constellation, as adopted by the International Astronomical Union in 1922, is 'Pyx'Pyxis lies in the plane of the Milky Way, although part of the eastern edge is dark, with material obscuring our galaxy arm there. NGC 2818 is a planetary nebula which lies within a dim open cluster of magnitude 8.2.

History

The French astronomer Nicolas Louis de Lacaille first described the constellation as la Boussole (the Marine Compass) and gave Bayer designations to ten stars now named Alpha to Lambda Pyxidis (he skipped the Greek letter iota). He renamed it Pixis [sic] Nautica on his 1763 chart.The Greeks identified the four main stars of Pyxis as the mast of the great ship. Pyxis can be seen overlying the mast of Argo Navis in this plate from Urania's Mirror (1825). John Herschel (in 1844) attempted to resurrect the classical configuration by renaming it Malus (the "Mast"), a suggestion followed by Francis Baily, but Benjamin Gould restored La Caille's nomenclature. Johann Bode (1747–1826) created the constellation Lochium Funis (the "Log and Line," a nautical device once used for measuring speed and distance traveled at sea) around Pyxis but this did not survive. 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.

References


Found in HGS Manual on Page 108 Found in HGS Manual on Page 115