51 Peg is a Sun-like G-type star (about 1.07 solar masses, 5,761 K, 1.19 solar radii), 50 light-years from Earth. 51 Pegasi b, announced in 1995 by Michel Mayor and Didier Queloz, was the first exoplanet found orbiting a Sun-like star — a discovery that earned the 2019 Nobel Prize in Physics and proved planetary systems are common. 51 Peg b is a 0.61-Jupiter-mass companion, with an orbital period of 4.2 days, at 0.052 AU from its star, discovered in 1995 via radial velocity. 51 Peg b orbits well inside Earth's distance from the Sun.