Kepler-106 and Its Four Planets

Kepler-106 is a star located 1450 light-years away, and four planets have been reported orbiting it. The host star is 4.83 billion years old, with a mass of 1 solar masses, a radius of 1.04 solar radii, and a temperature of 5860 K. All four planets were discovered by transit, the method in which a planet passes in front of its star from our viewpoint and causes a small dip in observed brightness.

Kepler-106 b and Kepler-106 d are both Sub-Earths, meaning their radii are smaller than Earth's. Kepler-106 b has a radius of 0.82 Earth radii, a reported upper limit of 5.3 Earth masses, and an orbital period of 6.16 days. Kepler-106 d has a radius of 0.95 Earth radii, a reported upper limit of 8.1 Earth masses, and an orbital period of 24 days.

Kepler-106 c and Kepler-106 e are Neptune-like planets, a class whose radii reach up to 4 times Earth's. Kepler-106 c has a radius of 2.5 Earth radii and a mass of 10.4 Earth masses, with a mean density of 3.68 g/cm³, 0.668 times Earth's. Its orbital period is 13.6 days. Kepler-106 e has a radius of 2.56 Earth radii and a mass of 11.2 Earth masses, with a mean density of 3.67 g/cm³, 0.666 times Earth's. Its orbital period is 43.8 days. Among the listed planets, Kepler-106 b has the shortest year by reported estimates, and Kepler-106 e has the longest year by reported estimates. Kepler-106 b also has the smallest radius by reported estimates, while Kepler-106 e has the largest.