Ursa Major (The Great Bear) is the constellation of which the asterism the Big Dipper is a part; the first star in the handle of the Big Dipper is Alioth (Epislon Ursae Majoris). Despite its Latin name, Alioth is, at the second magnitude, the brightest star both in the Dipper and the Great Bear. The name "Alioth" is corrupted Arabic. Though usually translated as "The Goat's Fat Tail" some sources have it as "The Dark Horse." In Arabic astrology it is also referred to as one of the "Three Sisters in Mourning." It is the 32nd star in the Nautical Almanac.
Alioth is a young blue-white star in its Main Sequence. It is about 50 million years old, it lies 83 light years from Earth, it is about three times as massive as the Sun and roughly four times the size, 108 times as bright, and burns at about 20,000 degrees Fahrenheit, twice as hot as our Sun.
When looked at through a spectrometer it evidences a strange stratification of its internal elements, the cause of which has been put down to the extreme tilt of its magnetic axis (90 degrees to that of its rotational axis) or possibly the gravitational pull of an unseen companion planet. It is a variable star that fluctuates about one magnitude ever six days.
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