<Tr> <Td> SIMBAD </Td> <Td> data </Td> </Tr> <Tr> <Td> ARICNS </Td> <Td> data </Td> </Tr> <P> Proxima Centauri (from Latin, meaning' nearest (star) of Centaurus'), or Alpha Centauri C, is a red dwarf, a small low - mass star, about 4.25 light - years (1.30 pc) from the Sun in the constellation of Centaurus . It was discovered in 1915 by the Scottish astronomer Robert Innes, the Director of the Union Observatory in South Africa, and is the nearest - known star to the Sun . With an apparent magnitude of 11.05, it is too faint to be seen with the naked eye . Proxima Centauri forms a third component of the Alpha Centauri trinary star system, currently with a separation of about 12,950 AU (1.94 trillion km) and an orbital period of 550,000 years . At present Proxima is 2.18 ° to the southwest of Alpha Centauri . </P> <P> Because of Proxima Centauri's proximity to Earth, its angular diameter can be measured directly . The star is about one - seventh the actual diameter of the Sun . It has a mass about an eighth of the Sun's mass (M), and its average density is about 33 times that of the Sun . Although it has a very low average luminosity, Proxima is a flare star that undergoes random dramatic increases in brightness because of magnetic activity . The star's magnetic field is created by convection throughout the stellar body, and the resulting flare activity generates a total X-ray emission similar to that produced by the Sun . The mixing of the fuel at Proxima Centauri's core through convection and its relatively low energy - production rate mean that it will be a main - sequence star for another four trillion years, or nearly 300 times the current age of the universe . </P>

Where is proxima centauri in the night sky