Proxima Centauri b (or Proxima b) is an exoplanet orbiting in the habitable zone of the red dwarf star Proxima Centauri, which is the closest star to the Sun and part of the triple star system Alpha Centauri. It is approximately 4.2 ly from Earth in the constellation Centaurus, making it and Proxima c the closest known exoplanets to the Solar S
