Ursa Minor (Latin: "Smaller Bear", contrasting with Ursa Major), also known as the Little Bear, is a constellation in the northern sky. Like the Great Bear, the tail of the Little Bear may also be seen as the handle of a ladle, whence the name Little Dipper. It was one of the 48 constellations listed by the 2nd century astronomer Ptolemy, and remains one of the 88 modern constellations. Ursa Minor is notable as the location of the north celestial pole, although this will change after some centuries due to the precession of the equinoxes.
Ursa Minor is colloquially known as the Little Dipper because its seven brightest stars seem to form the shape of a dipper (ladle or scoop). The star at the end of the dipper handle is Polaris, the North Star. Polaris can also be found by following a line through the two stars which form the end of the "bowl" of the Big Dipper, a nearby asterism found in the constellation Ursa Major.
Polaris (α UMi), the brightest star in the constellation, is a yellow supergiant shining at 2.02 apparent magnitude . It belongs to the rare class of Cepheid variable stars. Only a bit less bright is β UMi (Kochab), a 2.08 orange giant star.
The four stars in the "bowl" of the little dipper are unusual in that they are of second, third, fourth and fifth magnitude. Hence they provide an easy guide to determining what magnitude stars are visible, useful for city dwellers or testing your eyesight.
Deep sky objects
Ursa Minor Dwarf, a dwarf galaxy, is located in the area of the constellation.
History and mythology
Ursa Minor is commonly visualized as a baby bear with an unusually long tail. The tail was said to have been lengthened from that usually expected for a bear, because of its being held by the tail and spun around the pole.(The center of the sky)
Ursa Minor and Ursa Major were related by the Greeks to the myth of Callisto and Arcas. However, in a variant of the story, in which it is Boötes that represents Arcas, Ursa Minor was considered to represent a dog. This is the older tradition which sensibly explains both the length of the tail and the obsolete alternate name of Cynosura (the dog's tail) for Polaris, the North Star.
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