Corona Australis was known to the Greeks not as a crown but as a wreath, which is how it is depicted on old star maps. Aratus did not name it as a separate constellation but referred to it as a circlet of stars beneath the forefeet of Sagittarius. Perhaps it has slipped off the archer’s head. Its first mention as a separate constellation appears to be in the first century BC by the Greek astronomer and mathematician Geminus of Rhodes in his survey of astronomy called Introduction to the Phenomena.
Corona Australis, at the forefeet of Sagittarius, in the Uranographia of Johann Bode (1801).
Ptolemy listed 13 stars in Corona Australis, although one of them has since been reassigned to the modern constellation Telescopium which adjoins it, as Alpha Telescopii. None of its stars is brighter than fourth magnitude and there seem to be no legends associated with it, unless this is the crown placed in the sky by Dionysus after retrieving his dead mother from the Underworld. Hyginus gives this myth under the Northern Crown (Corona Borealis) but it seems out of place there and he may have confused the two constellations. If so, the wreath would be made of myrtle leaves, for Dionysus left a gift of myrtle in Hades in return for his mother, and the followers of Dionysus wore crowns of myrtle.
Chinese astronomers saw the stars of Corona Australis as forming a large turtle with a strong shell, Bie, positioned on the banks of the celestial river, the Milky Way. Fourteen stars were involved. One depiction restricts Bie to the stars of present-day Corona Australis, although an alternative view shows it extending further south to include Alpha Telescopii. Not far away in the Chinese sky was another turtle, Gui, in the area we know as Ara.
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