Kepler-42 is a cool M-dwarf (about 0.13 solar masses, 3,068 K, 0.17 solar radii), 40.1 light-years from Earth. Kepler-42 hosts three planets smaller than Earth around a tiny red dwarf, packed well inside Mercury's orbit. Kepler-42 c is a planet with 0.7 Earth radii, with an orbital period of 10.9 hours, at 0.006 AU from its star, and an equilibrium temperature near 720 K, discovered in 2011 via transit. Kepler-42 b is a planet with 0.8 Earth radii, with an orbital period of 1.2 days, at 0.012 AU from its star, and an equilibrium temperature near 519 K, discovered in 2011 via transit.