![]() It is a series of three pairs of stars found along the southern border of the constellation. By visually tracing a line from Merak through Dubhe (1 unit) and continuing for 5 units, one's eye will land on Polaris, accurately indicating true north.Īnother asterism representing three pairs of footprints of a leaping gazelle is recognized in Arab culture. The stars Merak (β Ursae Majoris) and Dubhe (α Ursae Majoris) are known as the "pointer stars" because they are helpful for finding Polaris, also known as the North Star or Pole Star. Ursa Major and Ursa Minor in relation to Polaris A few other such stars have been identified, and together they are called the Ursa Major Moving Group. Įxcept for Dubhe and Alkaid, the stars of the Big Dipper all have proper motions heading toward a common point in Sagittarius. With a magnitude of 1.85, Alkaid is the third-brightest star of Ursa Major. η Ursae Majoris, known as Alkaid, meaning the "end of the tail".Mizar, which means "girdle", forms a famous double star, with its optical companion Alcor (80 Ursae Majoris), the two of which were termed the "horse and rider" by the Arabs. ζ Ursae Majoris, Mizar, the second star in from the end of the handle of the Big Dipper, and the constellation's fourth-brightest star.It is also the brightest of the chemically peculiar Ap stars, magnetic stars whose chemical elements are either depleted or enhanced, and appear to change as the star rotates. Alioth is the brightest star of Ursa Major and the 33rd-brightest in the sky, with a magnitude of 1.76. ε Ursae Majoris, known as Alioth, a name which refers not to a bear but to a "black horse", the name corrupted from the original and mis-assigned to the similarly named Alcor, the naked-eye binary companion of Mizar. ![]() δ Ursae Majoris, or Megrez, meaning "root of the tail", referring to its location as the intersection of the body and tail of the bear (or the ladle and handle of the dipper).γ Ursae Majoris, known as Phecda ("thigh"), with a magnitude of 2.44.β Ursae Majoris, called Merak ("the loins of the bear"), with a magnitude of 2.37.α Ursae Majoris, known by the Arabic name Dubhe ("the bear"), which at a magnitude of 1.79 is the 35th-brightest star in the sky and the second-brightest of Ursa Major.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. ![]() Visible at latitudes between + 90° and − 30°.īest visible at 21:00 (9 p.m.) during the month of April.
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