KOI-94 and Its Four-Planet System

KOI-94 is a star 1560 light-years away with four planets, all discovered by transit in 2013. The star is 3.16 billion years old, has 1.28 solar masses, 1.52 solar radii, and a temperature of 6180 K.

KOI-94 b is a Super-Earth with an orbital period of 3.74 days, a radius of 1.71 Earth radii, and a mass of 10.5 Earth masses. Its mean density is 11.6 g/cm³, 2.1 times Earth's. KOI-94 c orbits every 10.4 days; it is a Jupiter-like planet with a radius of 4.32 Earth radii and a mass of 15.6 Earth masses, and its mean density is 1.07 g/cm³, 0.193 times Earth's. KOI-94 d has an orbital period of 22.3 days, a radius of 11.3 Earth radii, and a mass of 106 Earth masses; its mean density is 0.408 g/cm³, 0.0741 times Earth's. KOI-94 e, also Jupiter-like, completes an orbit in 54.3 days and has a radius of 6.56 Earth radii and a mass of 35 Earth masses, with a mean density of 0.683 g/cm³, 0.124 times Earth's.

Among the listed planets, KOI-94 b has both the shortest year and the smallest radius. KOI-94 c has the second-shortest year, the second-smallest radius, and the second-smallest reported mass. KOI-94 e has the longest year and the second-largest radius and reported mass, while KOI-94 d has the largest radius and reported mass and the second-longest year. The star's reported mass and radius estimates are larger than the Sun's, and its reported temperature is hotter than the Sun's.