K2-19 is a Sun-like G-type star (about 0.89 solar masses, 5,350 K, 0.82 solar radii), 290 light-years from Earth. K2-19 d is a 6.2-Earth-mass planet, with an orbital period of 2.5 days, at 0.035 AU from its star, and an equilibrium temperature near 1,258 K, on an eccentric orbit (e ≈ 0.44), discovered in 2016 via transit. K2-19 b is a 0.10-Jupiter-mass companion, with an orbital period of 7.9 days, on an eccentric orbit (e ≈ 0.10), discovered in 2015 via transit. Mutual gravitational tugs between the planets can slowly reshape their orbits, preserving clues to the system's assembly.