'''Arcturus''', also known as '''Alpha Boötis''', is a star located some 36.7 light years from our [[Sun]]. It is the brightest star in the constellation [[Boötes]]. Arcturus is the fourth brightest star overall in the night sky after [[Sirius]], [[Canopus]], and [[Alpha Centauri|Alpha Centauri AB]] (the two stars are too close to resolve separately with the unaided eye), and the brightest one located in the northern celestial hemisphere, with an apparent magnitude of -0.05.<ref>http://www.atlasoftheuniverse.com/stars.html</ref> Arcturus is a single star, although in the 1990's it was thought to possibly have a stellar companion.<ref>http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1999PASP..111..556T&db_key=AST&high=3bd70156a918794</ref> | '''Arcturus''', also known as '''Alpha Boötis''', is a star located some 36.7 light years from our [[Sun]]. It is the brightest star in the constellation [[Boötes]]. Arcturus is the fourth brightest star overall in the night sky after [[Sirius]], [[Canopus]], and [[Alpha Centauri|Alpha Centauri AB]] (the two stars are too close to resolve separately with the unaided eye), and the brightest one located in the northern celestial hemisphere, with an apparent magnitude of -0.05.<ref>http://www.atlasoftheuniverse.com/stars.html</ref> Arcturus is a single star, although in the 1990's it was thought to possibly have a stellar companion.<ref>http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1999PASP..111..556T&db_key=AST&high=3bd70156a918794</ref> |