Mnemosyne — Classical Greek Myth Library

After Callisto, companion of Artemis, was turned into a bear—by Zeus to hide her from Hera, or by Artemis in anger, or by Hera in jealousy—and after she had borne (or already borne) Arcas, the story ends in the sky. Zeus places Callisto among the constellations as the Great Bear (Arctos, Helice, Ursa Major). Arcas, nearly killing his mother in bear-shape while hunting, or simply taken up with her, becomes Arctophylax (“Bear-Watcher”) or Boötes beside her. Hera, still hostile, persuades Tethys and Oceanus never to let the Bear set in their waters—hence the classical aetiology that Ursa Major circles always above the horizon in Greek latitudes and never bathes in the Ocean. Astronomical handbooks and Aratus preserve the Bear as Callisto’s lasting form: hunters still see the Arcadian nymph in the turning Wain. The catasterism thus completes the Arcadian ethnography (Arcas eponym) with a cosmic prohibition born of Hera’s spite. Catalogue the stellification apart from the seduction-and-metamorphosis narrative so Arctos and the never-setting aetiology stand clear.