The stars of the Rigel Kentaurus system represent the nearest stars to the earth other than the sun.
A Triple Star System
The Rigel Kentaurus system is a triple star system. The A star primary is of spectral type G2V, that is yellow star of the same type as our sun. This star is slightly larger in mass and diameter than the sun, and slightly more luminous.
The B component of the system is separated by about 24 AU from A (that is somewhat greater than the distance between the sun and planet Uranus) and revolves with a period of 79.9 years.
Rigel Kentaurus C is a cool red M5.5Ve main sequence dwarf with a Apparent Magnitude of 11.1, corresponding to a luminosity of about 1/17,000 that of the sun. This star is known as Proxima Centauri.
The Nearest Star
Proxima is separated from the other two stars of the system by about 1/6 of a ly. At 4.22 ly from the earth, Proxima is actually the nearest single star to the earth.
See this German site for a nice three-dimensional representation of our nearby neighbor stars.
See this page for more information on the Rigel Kentaurus system.