Arcturus
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.”
The Editors of Encyclopaedia Britannica This article was most recently revised and updated by Erik Gregersen.
Citation Information
Article Title:
Arcturus
Website Name:
Encyclopaedia Britannica
Publisher:
Encyclopaedia Britannica, Inc.
Date Published:
07 November 2026
Access Date:
November 13, 2026