K2-239 is a cool M-dwarf (about 0.40 solar masses, 3,420 K, 0.36 solar radii), 31.1 light-years from Earth. K2-239 b is a planet with 1.1 Earth radii, with an orbital period of 5.2 days, at 0.044 AU from its star, and an equilibrium temperature near 502 K, discovered in 2018 via transit. K2-239 c is a planet with 1.0 Earth radii, with an orbital period of 7.8 days, at 0.058 AU from its star, and an equilibrium temperature near 427 K, discovered in 2018 via transit.