At just over 4.25 light years or about 25 trillion miles, from Earth, the Alpha Centauri system of three stars is the nearest to us.

Alpha Centauri system include a pair called “A” and “B,” (AB for short) which orbit relatively close to each other. Alpha Cen A is a near twin of our Sun in almost every way, including age, while Alpha Cen B is somewhat smaller and dimmer but still quite similar to the Sun. The third member, Alpha Cen C (also known as Proxima), is a much smaller red dwarf star that travels around the AB pair in a much larger orbit that takes it more than 10 thousand times farther from the AB pair than the Earth-Sun distance. Proxima currently holds the title of the nearest star to Earth, although AB is a very close second.

Alpha Centauri. What Does the Closest Stellar System Conceal?