HD 159243 and Its Two Planets

HD 159243 is a G0 V star located 239 light-years from Earth, and two planets orbit it: HD 159243 b and HD 159243 c. The star has a mass of 1.13 solar masses, which is larger than the Sun's mass, and a radius of 1.12 solar radii, which is larger than the Sun's radius. Its temperature is 6120 K, hotter than the Sun's, and its age is 1.25 billion years. The G0 V spectral type identifies it as a Sun-like, main-sequence star.

HD 159243 b was discovered in 2013 using the radial velocity method, which detects the wobble a planet's gravity induces in its star's motion. Its minimum mass is 359 Earth masses, meaning its true mass is at least that value, and this minimum mass is larger than Earth's and roughly 1.13 times Jupiter's mass. Among the listed planets, it has the shortest year by reported estimates, an orbital period of 12.6 days, and the smallest minimum mass, 359 Earth masses.

HD 159243 c was also discovered in 2013 by radial velocity. Its minimum mass is 604 Earth masses, larger than Earth's and roughly 1.9 times Jupiter's mass. Among the listed planets, it has the longest year by reported estimates, an orbital period of 248 days, and the largest minimum mass, 604 Earth masses.