Alpha Centauri

noun

Astronomy. a triple-star system that is the brightest celestial object in the constellation Centaurus.
Also called Rigel Kentaurus.

Origin of Alpha Centauri

< New Latin: Alpha of Centaurus

Scientific definitions for alpha centauri

Alpha Centauri
[ ăl′fə sĕn-tôr′ē ]

A triple star system in the constellation Centaurus that is the third brightest star in the night sky, with an apparent magnitude of -0.27, and the star nearest to Earth, at a distance of about 4.2 light-years. The two brighter stars, Alpha Centauri A and B, form a binary star system, which is orbited by Proxima Centauri, a smaller, dimmer star.