HD 81688 is an orange K-type dwarf (about 1.07 solar masses, 4,797 K, 11.1 solar radii), 85.7 light-years from Earth. HD 81688 b is a 1.65-Jupiter-mass companion, with an orbital period of 184 days, at 0.648 AU from its star, discovered in 2007 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 81688 b circles its star within the inner habitable zone.