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Thuban

Alpha Draconis, 11 Draconis

White Star in Draco

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Proper Name	Thuban
Bayer Designation	Alpha Draconis
Flamsteed Number	11 Draconis
HR (BSC)	5291
HD	123299
Constellation	Draco
Right Ascension	14h 4m 23s
Declination	+64° 22' 33"
Distance	303 light years 93 parsecs
Magnitude	Apparent: +3.7 Absolute: -1.2
Spectral Class	A0 White Giant
Optimum Visibility	May (Usually visible from northern latitudes)
Notes	Thuban lies close to the path of the northern Precession Circle, so that at times it falls very near the Northern Celestial Pole (t was Earth's northern Pole Star for a period of some 2,000 years ending in about 1900 BCE). It is a binary system, with a dwarf companion star orbiting the primary white giant.

Though it is a faint star in a sparse region of the sky, Thuban is not difficult to locate. It lies halfway between the 'bowl' of the Little Dipper, and the 'handle' of the Big Dipper.

Though only of magnitude 3.7, and by no means the brightest star in its constellation, Thuban is nonetheless designated Alpha Draconis.

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