出典:Wikipedia
出典:『Wikipedia』 (2011/07/03 19:57 UTC 版)
Regulus (α Leo, α Leonis, Alpha Leonis) is the brightest star in the constellation Leo and one of the brightest stars in the night sky, lying approximately 77.5 light years from Earth. Regulus is a multiple star system composed of four stars which are organised into two pairs. The spectroscopic binary Regulus A consists of a blue-white main-sequence star and its companion which has not yet been directly observed, but is probably a white dwarf star. Located farther away is the pair Regulus B and Regulus C, which are dim main-sequence stars.