HD 199509 is a Sun-like G-type star (about 1.04 solar masses, 5,796 K), 24.3 light-years from Earth. HD 199509 b is a 0.14-Jupiter-mass companion, with an orbital period of 99.6 days, at 0.426 AU from its star, on an eccentric orbit (e ≈ 0.37), discovered in 2022 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.