Kepler-68 and Its Four Planets

Kepler-68 is a star located 470 light-years away with four planets orbiting it. The host star is 6.3 billion years old and has a mass of 1.08 solar masses and a radius of 1.24 solar radii, making both its reported mass and radius larger than the Sun's. Its temperature is 5790 K. The system includes a stellar companion, but the measurements here describe only the host star.

Kepler-68 b is a Super-Earth discovered by transit in 2013. It has a mass of 8.03 Earth masses and a radius of 2.36 Earth radii, both larger than Earth's, and orbits every 5.4 days, the shortest period among the listed planets. Its mean density is 3.38 g/cm³, 0.613 times Earth's.

Kepler-68 c is a Sub-Earth, also found by transit in 2013. Its radius of 0.979 Earth radii is smaller than Earth's, and it has a reported upper limit of 1.3 Earth masses. It orbits every 9.61 days, the second-shortest period among the listed planets.

Kepler-68 d and Kepler-68 e were both discovered by radial velocity. Kepler-68 d, found in 2013, has a minimum mass of 238 Earth masses and an orbital period of 633 days, the second-longest among the listed planets. Kepler-68 e, found in 2023, has a minimum mass of 86.4 Earth masses. Both minimum masses are larger than Earth's, and Kepler-68 e orbits every 3460 days, the longest period among the listed planets.