HD 18143 is an orange K-type dwarf (about 0.85 solar masses, 5,078 K), 22.5 light-years from Earth. HD 18143 b is a 10.8-Earth-mass planet, with an orbital period of 10.3 days, at 0.088 AU from its star, on an eccentric orbit (e ≈ 0.22), discovered in 2022 via radial velocity. HD 18143 c is a 10.00-Jupiter-mass companion, with an orbital period of 79.3 years, at 17.5 AU from its star, on an eccentric orbit (e ≈ 0.19), discovered in 2022 via radial velocity. Mutual gravitational tugs between the planets can slowly reshape their orbits, preserving clues to the system's assembly.