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Arcturus
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Also called:
Alpha Boötis
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Arcturus

star
Also known as: Alpha Boötis
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Encyclopaedia Britannica's editors oversee subject areas in which they have extensive knowledge, whether from years of experience gained by working on that content or via study for an advanced degree....
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Arcturus, the fourth brightest star in the night sky, and the brightest star in the northern constellation Boötes, with an apparent visual magnitude of −0.05. It is an orange-coloured giant star 36.7 light-years from Earth. It lies in an almost direct line with the tail of Ursa Major (the Great Bear); hence its name, derived from the Greek words for “bear guard.”

(List of Brightest Stars as Seen from Earth)

The Editors of Encyclopaedia Britannica This article was most recently revised and updated by Erik Gregersen.
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