HD 109271 and Its Two Known Planets

HD 109271 is a G-type dwarf, or G5 V, some 182 light-years away. Its mass is 1.05 solar masses, its temperature is 5780 K, and its age is 7.3 billion years. Two planets are known to orbit this star.

HD 109271 b was discovered in 2013 by the radial velocity method, which detects the wobble a planet's gravity induces in its star. Its minimum mass is 17.2 Earth masses and its orbital period is 7.85 days. HD 109271 c, also found in 2013 by radial velocity, has a minimum mass of 24.2 Earth masses and an orbital period of 30.9 days. Both minimum masses are lower bounds on the planets' true masses, and both are larger than Earth's. Among the listed planets, HD 109271 b has the shortest year, at 7.85 days, and the smallest minimum mass, at 17.2 Earth masses, while HD 109271 c has the longest year, at 30.9 days, and the largest minimum mass, at 24.2 Earth masses. The star's reported mass estimate is larger than the Sun's.