Proxima Centauri, or Alpha Centauri C, is the title holder of being our closest neighboring star (Glass (2007); Anglada-Escudé et al. (2016a)), other than Sun, despite being at a whopping distance of 4.25 light-years (Lurie et al. (2014)). A part of the Alpha Centauri star system it is the third star with other two being, Alpha Centauri A (Rigil Kentaurus) and Alpha Centauri B, a pair orbiting around each other. The separation between the two stars and Proxima is estimated to be 13,000 +300/-100 astronomical units (Kervella et al. (2017)).
Proxima Centauri (pCen from here on) is a red dwarf of M6Ve spectral type (Torres et al. (2006)) residing in the constellation Centaurus. It hosts a terrestrial planet dubbed Proxima b within its habitable zone (Anglada-Escudé et al. (2016b)). Compared to the Sun its absolute visual magnitude is 15.6 (Kamper & Wesselink (1978)), apparent magnitude of 11.13 (Jao et al. (2014)), luminosity is 0.17% (Doyle & Butler (1990)) with most of its light emitted in the infrared region (Leggett (1992)).
Being the closest star to us, it is one of the most extensively studied star estimates of the mass of pCen are around 12.3% of the Solar Mass or 129 Jupiters (Ségransan et al. (2003)) and of the radius being around 14.1% of the Solar Radius (Demory et al. (2009)).
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