Alpha Centauri

noun

Alpha Cen·​tau·​ri -sen-ˈtȯr-ē 

astronomy

: a binary star of magnitude zero that is the brightest star in the southern constellation Centaurus

The plot centered on scientists John and Maureen Robinson and their three children, who in 1997 leave an overpopulated Earth to colonize a planet near Alpha Centauri.

—Diane Tedeschi, Air & Space Smithsonian, August/September 1988

Note: What is visible in the night sky as the star Alpha Centauri is actually a binary system: two stars bound together gravitationally.

Word History

Etymology

borrowed from New Latin, "Alpha of Centaurus"

First Known Use

1777, in the meaning defined above

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