Flexi Says: Alpha Centauri is at 4.37 light-years from the Sun. Alpha Centauri is the closest star system and closest planetary system to Earth's Solar System. The Alpha Centauri system contains three stars, one binary star system and a third, small star that is gravitationally bound to the binary stars. This smaller star, Proxima Centauri, is the closest to the Sun (Sol) of the three.
