- Astronomy. a triple-star system that is the brightest celestial object in the constellation Centaurus.
Origin of Alpha Centauri
< New Latin: Alpha of Centaurus
Also called Rigel Kentaurus.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
- 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.
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