Kepler-235: A Red Dwarf and Its Four Worlds

Kepler-235 is an M0 V star located 1400 light-years away. This spectral class marks it as an M-type main-sequence dwarf - a small, cool red dwarf - with a temperature of 4000 K. Its mass is 0.507 solar masses and its radius is 0.495 solar radii, both smaller than the Sun's, and its temperature is cooler than the Sun's. The star is 6 billion years old. Four planets orbit this host.

All four planets were discovered by the transit method in 2014, when each passed in front of its star from our viewpoint and caused a small dip in observed brightness. Kepler-235 b, a Super-Earth, orbits every 3.34 days and has a radius of 2.23 Earth radii. Kepler-235 c, an Earth-like planet, orbits every 7.82 days and has a radius of 1.28 Earth radii. Kepler-235 d, a Super-Earth, orbits every 20.1 days with a radius of 2.05 Earth radii. Kepler-235 e, also a Super-Earth, orbits every 46.2 days and has a radius of 2.22 Earth radii. Every one of these radii is larger than Earth's.

Among the listed planets, Kepler-235 b has the shortest year by reported estimates, at 3.34 days, while Kepler-235 e has the longest, at 46.2 days. Kepler-235 b also has the largest radius by reported estimates, at 2.23 Earth radii, and Kepler-235 c has the smallest, at 1.28 Earth radii.