KOI-984: A Cool, Compact Star With Two Known Planets

KOI-984 is a star 824 light-years away with two planets orbiting it. The host star has a mass of 0.992 solar masses, a radius of 0.871 solar radii, and a temperature of 5510 K. Its reported radius estimate is smaller than the Sun's, and its reported temperature is cooler than the Sun's.

Both planets were discovered in 2022. KOI-984 b is a Jupiter-like planet found by transit, the small dip in brightness when a planet crosses in front of its star. It has a radius of 4.3 Earth radii, larger than Earth's, and an orbital period of 4.29 days. KOI-984 c was found through transit timing variations, in which slight changes in a transiting planet's schedule reveal another body. It has a mass of 210 Earth masses, larger than Earth's, and an orbital period of 21.5 days. Among the listed planets, KOI-984 b has the shortest year by reported estimates at 4.29 days, while KOI-984 c has the longest at 21.5 days.