Alpha Centauri

The closest star system to the Sun, at a distance of more than four light-years, Alpha Centauri consists of three stars. Two of the stars -- one of which is similar to the Sun, while the other is a little smaller and cooler -- form a tight pairing. The third, known as Proxima Centauri, is about one-tenth of a light-year from the other two, and is a red dwarf star. It is closer to Earth than the other two stars, but it is so faint that it is not visible to the unaided eye.


Facts and Figures The biggest, farthest and fastest in the...

Radio Programs

Alpha Centauri Planet Taking the measure of a planet Saturday, September 12, 2015
Proxima Centauri Discovering our closest neighbor Thursday, September 10, 2015
Alpha Centauri Putting three stars on the scales Monday, May 25, 2015
Alpha Centauri Planet A nearby planetary neighbor Sunday, April 21, 2013
The Llama The sparkling eyes of the llama Saturday, May 26, 2012

Featured Images

Artist's concept of Alpha Centauri A and B, plus a planet
Busy Neighbor Monday, May 25, 2015
Artist's depiction of planet orbiting Alpha Centauri B
Close Neighbor Sunday, April 21, 2013


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