Kepler-256 and Its Four Super-Earths

Kepler-256 is a star located 3350 light-years away. It is 9.55 billion years old, has a mass of 0.97 solar masses, and a radius of 1.14 solar radii. Its temperature is 5610 K, cooler than the Sun's. Four planets are known to orbit this star, all discovered by transit in 2014. A transit occurs when a planet passes in front of its star from our viewpoint, causing a small dip in observed brightness.

All four planets are classified as Super-Earths, meaning their radii reach up to 2.5 times Earth's radius. Kepler-256 b has an orbital period of 1.62 days and a radius of 1.59 Earth radii. Among the listed planets, it has the shortest year and the smallest radius. Kepler-256 c has an orbital period of 3.39 days and a radius of 2.15 Earth radii. Among the listed planets, it has the second-shortest year and the second-smallest radius. Kepler-256 d has an orbital period of 5.84 days and a radius of 2.48 Earth radii. Among the listed planets, it has the second-longest year and the largest radius. Kepler-256 e has an orbital period of 10.7 days and a radius of 2.35 Earth radii. Among the listed planets, it has the longest year and the second-largest radius. Each planet's reported radius estimate is larger than Earth's.