About Kepler-1257 b
Kepler-1257 b is a rare exoplanet. It lies about 3,607.1 light-years from Earth, shines at apparent magnitude 15.64, has an equilibrium temperature near 1,252 K and spans roughly 1.52 Earth radii.
It orbits closer to its star than Mercury does to the Sun, completing a lap in less time than Mercury takes.