One of the 12 constellations introduced at the end of the 16th century by the Dutch navigators Pieter Dirkszoon Keyser and Frederick de Houtman after their pioneer observations of the southern skies. Grus represents a long-necked wading bird, the crane.
The constellation was first shown on a celestial globe by Petrus Plancius in 1598 under the name Krane Grus, respectively Dutch and Latin words for crane, although on a later Plancius globe issued posthumously in 1625 it bore the alternative title of Phoenicopterus, the flamingo. As another identification, de Houtman called it Den Reygher, the heron, in his southern star catalogue of 1603. Johannes Bayer adopted the name Grus for the constellation in his Uranometria atlas of 1603, and the original identification as a crane won out.
Grus cranes its neck in the Uranographia of Johann Bode (1801).
Grus was formed from stars south of Piscis Austrinus, the Southern Fish. In fact, the star we now know as Gamma Gruis, marking the crane’s head, was taken over from the original Greek Piscis Austrinus – Ptolemy listed it in the Almagest as the star on the tip of the tail. Bayer and others straightened out the tail of Piscis Austrinus so that it did not overlap with the head of Grus.
The constellation’s brightest star, second-magnitude Alpha Gruis, is named Alnair, from an abbreviation of the Arabic meaning ‘the bright one from the fish’s tail’; this name arose because Arab astronomers in the 16th century had extended the tail of Piscis Austrinus southwards beyond the Ptolemaic limits of the constellation.
There are no legends associated with Grus, but in Greek mythology the crane was sacred to Hermes.
Being so far south, the stars of Grus barely featured in the Chinese constellation system. However, part of the Chinese constellation Baijiu lay in this area, representing a kind of celestial skip for waste. Baijiu consisted of four stars forming a tub shape. The present-day Gamma Gruis could have been one of them, and possibly Lambda Gruis was a member too. The rest of Baijiu lay to the north in Piscis Austrinus.
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