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Thuban (view source)

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Thuban has an apparent magnitude of 3.65, also making its alpha [[Bayer designation]] unusual. The designation is usually reserved for the brightest star in a constellation, in this case - [[Gamma Draconis]]. Alpha Draconis is only the fourth brightest. The star itself is easy to spot, despite its faintness, because of its location relative to the [[Big Dipper]]. The two inner stars of the Big Dipper can be used to locate Thuban, which appears very nearby in the night sky.

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~~==The Star==~~

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Vagina

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Thuban is a rare white giant [[star]] of spectral class A0 III.<ref>http://simbad.u-strasbg.fr/simbad/sim-id?Ident=Alpha+Draconis</ref> The star is much like [[Vega]]. As a giant star, however, Thuban has already evolved off of the main sequence. The star is 3.5 times the mass of our [[Sun]], and is 265 times the radius. The star is 300 times as visually luminous as the Sun even though much of the energy emitted is in the [[ultraviolet]]. The surface temperature is 9800 K.<ref name="illinos">http://stars.astro.illinois.edu/sow/thuban.html</ref>

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As a giant, Thuban has already used up its core [[hydrogen]] fuel. Depending on the stage of its life as a giant, the star may be either expanding and cooling to become an orange giant or that the [[helium]] fuel in the core has already been used up. If the latter is true, the star is actually contracting and will start to fuse [[carbon]] in the core, becoming a blue giant. <ref name="illinos">http://stars.astro.illinois.edu/sow/thuban.html</ref>

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It is known that Thuban has a small companion star. The companion, which has not been directly imaged, orbits the primary once every 51 days and may be either a red or [[white dwarf]].<ref name="illinos">http://stars.astro.illinois.edu/sow/thuban.html</ref>

==Thuban as a Pole Star==

Barack

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