Alpha Centauri

Alpha Cen·​tau·​ri | \ -sen-ˈtȯr-ē How to pronounce Alpha Centauri (audio) \

Definition of Alpha Centauri

: 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.

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First Known Use of Alpha Centauri

1777, in the meaning defined above

History and Etymology for Alpha Centauri

borrowed from New Latin, “Alpha of Centaurus”

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Time Traveler for Alpha Centauri

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The first known use of Alpha Centauri was in 1777

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Cite this Entry

“Alpha Centauri.” Dictionary, Merriam-Webster, Accessed 4 Mar. 2021.

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