Kepler-401 and Its Three Planets

Kepler-401 is a star located 3150 light-years away. It is 3.39 billion years old, with a mass of 1.17 solar masses and a radius of 1.29 solar radii, and its temperature is 6180 K. Its reported mass and radius estimates are larger than the Sun's, and its reported temperature is hotter than the Sun's. Three planets orbit this host.

All three planets were discovered by transit, the dimming of a star's light when a planet passes in front of it. Kepler-401 b and Kepler-401 c were both found in 2014, while Kepler-401 d was found in 2016. All three are classified as Super-Earths, a size class reaching 2.5 times Earth's radius.

Kepler-401 b has an orbital period of 14.4 days and a radius of 1.71 Earth radii. Among the listed planets, it has the shortest year and the smallest radius. Kepler-401 c has an orbital period of 47.3 days and a radius of 2.15 Earth radii, giving it the second-shortest year and the second-smallest radius among the listed planets. Kepler-401 d has an orbital period of 184 days and a radius of 2.27 Earth radii. Among the listed planets, it has the longest year and the largest radius. Each planet's reported radius estimate is larger than Earth's.