HD 188641 is a Sun-like G-type star (about 1.07 solar masses, 5,897 K), 64.3 light-years from Earth. HD 188641 b is a 29.4-Jupiter-mass companion, with an orbital period of 39.9 years, at 12.0 AU from its star, 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. HD 188641 b orbits far from its host star. At 29.4 Jupiter masses, the companion lies near the dividing line between giant planets and brown dwarfs.