Proxima Centauri b (also called Proxima b) is an exoplanet orbiting within the habitable zone of the red dwarf star Proxima Centauri, the closest star to the Sun. It is located about 4.2 light-years (1.3 parsecs, 40 trillion km, or 25 trillion miles) from Earth in the constellation of Centaurus, making it the closest known exoplanet to the Solar System. It is unlikely to be habitable, as the planet is subject to stellar wind pressures of more than 2,000 times those experienced by Earth from the solar wind. More information about the planet's physical characteristics is needed for a proper evaluation.