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Published byHarold Preston Modified over 9 years ago
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The Big Dipper
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Many people mistakenly think that the Big Dipper is a constellation but it isn't, it is something called an asterism.
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An asterism is a star-pattern that is not a constellation. Asterisms may be contained within a single constellation or consist of stars belonging to different constellations. The Big and Little Dippers are asterisms within the constellations of Ursus Major and Ursus Minor.Ursus MajorUrsus Minor
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IN OTHER PARTS OF THE WORLD, THESE SEVEN STARS ARE KNOWN NOT AS A DIPPER, BUT AS SOME SORT OF A WAGON. WHERE EXACTLY DID THIS NAME COME FROM? NOBODY SEEMS TO KNOW. SOME BELIEVE THAT IT MAY HAVE ORIGINATED FROM AFRICA, WHERE IT WAS SOMETIMES SEEN AS A DRINKING GOURD. The Big Dipper is just one of the many names for the most recognizable asterism in the August sky.
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THE FACT THAT THE BIG DIPPER ALSO FORMED A BEAR TO AMERICAN INDIANS AND TO CULTURES OF THE OLD WORLD AND SIBERIA SUGGESTS THAT OUR URSA MAJOR IS A VERY ANCIENT STAR PATTERN. In America during the latter half of the 19th century, runaway slaves would "follow the Drinking Gourd" to the north and freedom. It was during this time that astronomy books began making reference to the "Great Dipper."
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The big dipper is located in the flank and tail of the constellation Ursa Major
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Ursa major means the Greater Bear in Latin. It is the third largest constellation in the sky.
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There are seven stars that make up the big dipper The stars that make up the Big Dipper follow the Greek alphabet, making them easy to remember. Thus, apart from alpha Ursae Majoris, the Dipper's bowl is made up of beta, gamma, and delta, then epsilon, zeta, and eta finish the asterism. Proper Name Bayer Designation Apparent Magnitude Distance (L Yrs) Dubheα UMa1.8124 Merakβ UMa2.479 Phecdaγ UMa2.484 Megrezδ UMa3.381 Aliothε UMa1.881 Mizarζ UMa2.178 Alkaidη UMa1.9101
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Dubhe the Yellow Giant The star, Alpha Uma is located in the right upper corner of the Big Dipper.
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Yellow Giant Star The star, alpha UMa (Dubhe: the Bear), is a yellow giant, about 25 times the size of the Sun,
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Megrez or Delta Ursae Majoris is one of the bowl stars closest to the handle. Megrez’s name comes from Arabic and means “the root of the tail.” Phecda or Gamma Ursae Majoris is one of the bowl stars that forms the bottom of the bowl closest to the handle. Phecda’s name comes from Arabic and means “the thigh.” Merak or Beta Ursae Majoris is the other bottom bowl stars in the Big Dipper. Merak’s name comes from Arabic and means “the lion.”
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Merak, Phecda & Megrez These three stars plus Dubhe make up the bowl part of the Big Dipper.
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White (A-type) Star Beta Ursae Majoris is named Merak, or "loin"; gamma is Phecda: thigh, and delta is called Megrez: root (or base) of the tail. These three are similar stars, all white (A-type) stars.
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Epsilon Uma “Alioth” When we go out onto the tail, we first encounter epsilon UMa, an alpha-CV type variable, and another A-type white star called Alioth. This star is one of the brightest in the constellation, although it is one of the more distant stars.
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Mizar Then comes zeta Ursae Majoris (Mizar: girdle or apron).
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Ursae Majoris, Benetnasch or Alkaid Finally we have eta Ursae Majoris, called either Benetnasch or Alkaid, both of which mean "chief of the mourners".
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1. " Wikipedia, the free encyclopedia." Big Dipper. Wikipedia, the free encyclopedia, n.d. Web. 25 Nov 2012.. 2. Dibon-Smith, Richard. "Ursa Major." The Constellations. Richard Dibon-Smith, 01 2012. Web. 25 Nov 2012.. 3. Rao, Joe. "See the big dipper in the summer night sky." Discovery News. Discovery News, 24 2012. Web. 11 Dec 2012..
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