star in the constellation Boötes From Wikipedia, the free encyclopedia
Arcturus (or α Boo, α Boötis, Alpha Boötis) of the constellation Boötes is the brightest star in the northern celestial hemisphere. With an apparent magnitude of −0.04, it is the fourth brightest star in the night sky, after −1.46 magnitude Sirius, −0.86 magnitude Canopus, and −0.27 magnitude Alpha Centauri.[1]
It is a relatively close star at only 36.7 light-years from Earth, and, together with Vega and Sirius, one of the most luminous stars in the Sun's neighborhood.
Arcturus is a type K1.5 IIIpe red giant star, with an absolute magnitude of −0.30. It has likely exhausted its hydrogen from the core and is now in its active red giant phase. It will continue to expand before entering the horizontal branch stage of its life cycle.[2] The diameter of Arcturus is around 35 million kilometers.
Seamless Wikipedia browsing. On steroids.
Every time you click a link to Wikipedia, Wiktionary or Wikiquote in your browser's search results, it will show the modern Wikiwand interface.
Wikiwand extension is a five stars, simple, with minimum permission required to keep your browsing private, safe and transparent.
