HD 29399 is an orange K-type dwarf (about 1.17 solar masses, 4,845 K, 4.50 solar radii), 44.2 light-years from Earth. HD 29399 b is a 1.57-Jupiter-mass companion, with an orbital period of 2.44 years, at 1.913 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 29399 b orbits at roughly the distance of Mars from the Sun.