Alpha Centauri is the closest star system to our sun. Officially third brightest star in the night sky after Sirius and Canopus, Alpha Centauri is actually a star cluster known as a binary system, consisting of Alpha Centauri A, Alpha Centauri B and Proxima Centauri. Proxima is closest at 4.22 light years, Alpha Centauri’s A & B roughly 4.35 light years or 39,900,000,000,000 km. from Earth.
This video speaks for itself – watch and ponder NASA’s warp drive vision of Alpha Centauri in two weeks.
http://earthsky.org/brightest-stars/alpha-centauri-is-the-nearest-bright-star