K2-240 is a cool M-dwarf (about 0.58 solar masses, 3,810 K, 0.54 solar radii), 72.9 light-years from Earth. K2-240 b is a planet with 2.0 Earth radii, with an orbital period of 6.0 days, at 0.051 AU from its star, and an equilibrium temperature near 586 K, discovered in 2018 via transit. K2-240 c is a planet with 1.8 Earth radii, with an orbital period of 20.5 days, at 0.116 AU from its star, and an equilibrium temperature near 389 K, discovered in 2018 via transit.