HD 102117 is a Sun-like G-type star (about 1.06 solar masses, 5,655 K, 1.23 solar radii), 39.6 light-years from Earth. HD 102117 b is a 0.17-Jupiter-mass companion, with an orbital period of 20.8 days, at 0.150 AU from its star, on an eccentric orbit (e ≈ 0.12), discovered in 2005 via radial velocity. The planet betrayed itself through the star's reflex motion — a technique that first revealed worlds around Sun-like stars in the 1990s and remains a workhorse of exoplanet discovery. The planet's marked eccentricity suggests past scattering events or perturbations from unseen companions.