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Line 3: − ==The Star==+ − − 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> − − 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> − − 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>
Conservative edit
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.
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.
Vagina
==Thuban as a Pole Star==
==Thuban as a Pole Star==