Bear is derived from the Celtic word for "bear", "artos". In ancient Greece, archaic cult of Artemis in bear form survived into Classical times at Brauron, where young Athenian girls passed an initiation right as "arktai" "she bears". For Artemis and one of her nymphs as a she-bear, see the myth of Callisto. The constellations of Ursa Major and Ursa Minor, the great and little bears, are named for their supposed resemblance to bears, from the time of Ptolemy. The nearby star Arcturus means "guardian of the bear", as if it were watching the two constellations. Ursa Major has been associated
Ursa Major Moving Group same direction at similar velocities, and also have similar chemical compositions and estimated ages. This evidence suggests to astronomers that the stars in the group share a common origin. Based on the numbers of its constituent stars, the Ursa Major Moving Group is believed to have once been an open cluster, having formed from a protostellar nebula approximately 500 million years ago. Since then, the sparse group has scattered over a region about 30 by 18 light-years, whose center is currently about 80 light-years away, making it the closest cluster-like object to Earth. The Ursa Major Moving Group was discovered