Betelgeuse, also known by its Bayer designation Alpha Orionis (α Orionis, α Ori), is the ninth brightest star in the night sky and second brightest star in the constellation of Orion, outshone by its brighter neighbour Rigel (Beta Orionis) almost all the time. Distinctly reddish-tinted, it is a semiregular variable star whose apparent magnitude varies between 0.2 and 1.2, the widest range of any first magnitude star. The star marks the upper right vertex of the Winter Triangle and center of the Winter Hexagon.
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Betelgeuse The second brightest star in the constellation Orion.
