HD 219415 and Its Lone Known Planet

HD 219415 is a K-type star 539 light-years from Earth. A spectral type of K0 III places it in a cooler class than the Sun, and its reported temperature of 4820 K is indeed cooler than the Sun's. The star is also more physically expansive than the Sun, with a mass of 1 solar masses and a radius of 2.9 solar radii; that radius estimate is larger than the Sun's.

One known planet orbits this host. HD 219415 b was discovered in 2012 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. The planet's minimum mass is 318 Earth masses, a lower bound on its true mass and larger than Earth's. It completes one orbit every 2090 days.