GJ 876 is a cool M-dwarf (about 0.32 solar masses, 3,294 K, 0.30 solar radii), 4.7 light-years from Earth. GJ 876 hosts the first planet discovered around a red dwarf, and its giant planets are locked in a Laplace resonance. GJ 876 d is a 6.8-Earth-mass planet, with an orbital period of 1.9 days, at 0.021 AU from its star, on an eccentric orbit (e ≈ 0.21), discovered in 2005 via radial velocity. GJ 876 c is a 0.71-Jupiter-mass companion, with an orbital period of 30.1 days, at 0.130 AU from its star, on an eccentric orbit (e ≈ 0.26), discovered in 2000 via radial velocity.

GJ 876 - System

Loading scenario…