Kepler-53: A Distant Star With Three Known Planets

Kepler-53 is a star 4460 light-years away with three planets orbiting it. The star is 3.89 billion years old, has 0.98 solar masses, 0.97 solar radii, and a temperature of 5770 K.

All three planets were found by transit, the method that detects a planet as it passes in front of its star and dims its light. Kepler-53 b and Kepler-53 c are Neptune-like planets discovered in 2012, while Kepler-53 d is a Super-Earth found in 2014.

Kepler-53 b has an orbital period of 18.6 days, a radius of 2.89 Earth radii, and a reported upper limit of 111 Earth masses. Kepler-53 c orbits every 38.6 days, has a radius of 3.17 Earth radii, and a reported upper limit of 36 Earth masses.

Kepler-53 d has the shortest year of the three at 9.75 days and a radius of 2.12 Earth radii. Among the listed planets, it has the smallest radius, while Kepler-53 c has the largest.