The three-letter constellation abbreviation "UMa" was adopted by the IAU in 1922. Ursa Major borders eight other constellations: Draco to the north and northeast, Boötes to the east, Canes Venatici to the east and southeast, Coma Berenices to the southeast, Leo and Leo Minor to the south, Lynx to the southwest and Camelopardalis to the northwest. In the equatorial coordinate system, the constellation stretches between the right ascension coordinates of 08 h 08.3 m and 14 h 29.0 m and the declination coordinates of +28.30° and +73.14°. In 1930, Eugène Delporte set its official International Astronomical Union (IAU) constellation boundaries, defining it as a 28-sided irregular polygon. Ursa Major covers 1279.66 square degrees or 3.10% of the total sky, making it the third largest constellation. From southern temperate latitudes, the main asterism is invisible, but the southern parts of the constellation can still be viewed. Ursa Major is visible throughout the year from most of the Northern Hemisphere, and appears circumpolar above the mid-northern latitudes. Its depiction on the flag of Alaska is a modern example of such symbolism. Ursa Major, along with asterisms it contains or overlaps, is significant to numerous world cultures, often as a symbol of the north. Two of its stars, named Dubhe and Merak ( α Ursae Majoris and β Ursae Majoris), can be used as the navigational pointer towards the place of the current northern pole star, Polaris in Ursa Minor. In particular, the Big Dipper's stellar configuration mimics the shape of the " Little Dipper". Ursa Major is primarily known from the asterism of its main seven stars, which has been called the " Big Dipper", "the Wagon", "Charles's Wain", or "the Plough", among other names. Today it is the third largest of the 88 modern constellations. In antiquity, it was one of the original 48 constellations listed by Ptolemy in the 2nd century AD, drawing on earlier works by Greek, Egyptian, Babylonian, and Assyrian astronomers. Its Latin name means "greater (or larger) bear", referring to and contrasting it with nearby Ursa Minor, the lesser bear. Ursa Major ( / ˈ ɜːr s ə ˈ m eɪ dʒ ər/ also known as the Great Bear) is a constellation in the northern sky, whose associated mythology likely dates back into prehistory.
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