HD 43691 is a Sun-like G-type star (about 1.32 solar masses, 6,093 K, 1.60 solar radii), 85.6 light-years from Earth. HD 43691 b is a 2.55-Jupiter-mass companion, with an orbital period of 37.0 days, at 0.238 AU from its star, on an eccentric orbit (e ≈ 0.08), 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 43691 b orbits well inside Earth's distance from the Sun.