HIP 97166: A K-Type Dwarf with Two Known Planets

HIP 97166 is a K0 V star located 215 light-years away, with two planets discovered in 2021. The star has a mass of 0.898 solar masses and a radius of 0.836 solar radii. Its temperature is 5200 K, and it is estimated to be 3.33 billion years old. Compared with the Sun, HIP 97166 is less massive, smaller, and cooler.

The two planets orbit this star. HIP 97166 b is a Super-Earth found by the transit method. Its radius is 2.48 Earth radii, larger than Earth's, and its mass is 19.1 Earth masses, also larger than Earth's. Its mean density is 6.9 g/cm³, 1.25 times Earth's. It completes an orbit in 10.3 days, the shortest period among the listed planets. HIP 97166 c was discovered by radial velocity, a method that detects the wobble a planet's gravity induces in its star. Its minimum mass is 8 Earth masses, larger than Earth's, and its orbital period is 16.4 days, the longest among the listed planets. A minimum mass is a lower bound on a planet's true mass, distinct from an ordinary mass estimate.