Alpha Centauri

noun

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

alpha centauri in Science

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.

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