HD 220197 b: A Giant Planet Orbiting a Sun-Like Star

HD 220197 is a G5 star located 210 light-years from Earth. Its spectral type places it in the same broad temperature class as the Sun, though its reported temperature of 5680 K is cooler than the Sun's. The star's reported mass estimate of 0.91 solar masses is smaller than the Sun's, and its radius is 0.98 solar radii. It is an old star, with an age of 10.2 billion years. One planet orbits this host.

That planet, HD 220197 b, was discovered in 2018 using the radial velocity method, which detects the wobble a planet's gravity induces in its star's motion; repeated wobbles reveal the planet and its orbital period. HD 220197 b has a minimum mass of 63.6 Earth masses, a lower bound on its true mass, and this minimum mass is larger than Earth's. The planet completes one orbit every 1730 days.