Alpha Centauri

American  

noun

1. Astronomy. a triple-star system that is the brightest celestial object in the constellation Centaurus.

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Alpha Centauri Scientific  

/ ăl′fəsĕn-tôr′ē /

1. 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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Etymology

Origin of Alpha Centauri

< New Latin: Alpha of Centaurus

Example Sentences

The signs were found in the star system Alpha Centauri by the powerful James Webb Space Telescope.

From BBC • Aug. 8, 2025

The group became stranded on a distant planet after their ship, the Jupiter 2, went off course en route to colonize a planet in the Alpha Centauri system.

From Los Angeles Times • Oct. 14, 2023

In the opening hours of the role-playing video game, it’s possible to land your spaceship on Earth’s moon or zip 16 light-years to Alpha Centauri.

From New York Times • Aug. 31, 2023

It took place at a location more than 8000 light-years away from our Earth in the direction of Alpha Centauri, between the constellations of Circinus and Centaurus.

From Space Scoop • Mar. 21, 2023

Thus one could imagine that one could create or find a wormhole that would lead from the vicinity of the Solar System to Alpha Centauri.

From "A Brief History of Time: And Other Essays" by Stephen Hawking