Kepler-784: A Distant Star With Two Super-Earths

Kepler-784 is a star located 4250 light-years away, and two planets have been found orbiting it. The star is 9.12 billion years old and has a mass of 1 solar masses, a radius of 1.32 solar radii, and a temperature of 5670 K. Its radius is larger than the Sun's, while its temperature is cooler than the Sun's.

Both planets were detected by the transit method, in which a planet passes in front of its star from our viewpoint and causes a small dip in observed brightness; repeated dips help establish orbital periods. Kepler-784 b, discovered in 2016, is a Super-Earth with a radius of 1.58 Earth radii and an orbital period of 31.6 days. Kepler-784 c, discovered in 2023, is also a Super-Earth, with a radius of 1.55 Earth radii and an orbital period of 17.2 days. Both planets are larger than Earth, and among the listed planets Kepler-784 b has the largest radius, while Kepler-784 c has the smallest radius.

Among the listed planets, Kepler-784 c has the shortest year, at 17.2 days, and Kepler-784 b has the longest year, at 31.6 days. A Super-Earth reaches up to 2.5 times Earth's radius; these size classes describe radius rather than composition.