HD 160691 and Its Four Planets

HD 160691 is a star 50.9 light-years away with a spectral type of G3IV/V. Its reported mass estimate is larger than the Sun's, its reported radius estimate is larger than the Sun's, and its reported temperature of 5780 K is hotter than the Sun's. The star is 7.96 billion years old and has 1.15 solar masses and 1.33 solar radii. Four planets are known to orbit it.

All four were found by the radial velocity method, which measures the wobble a planet's gravity induces in its star's motion. HD 160691 b was discovered in 2000 and has a reported upper limit of 1366.6621501 Earth masses and an orbital period of 645 days. HD 160691 c, discovered in 2004, has a reported upper limit of 1398.4449908 Earth masses and a period of 3950 days. HD 160691 d, also discovered in 2004, has a period of 9.64 days. HD 160691 e, discovered in 2006, has a reported upper limit of 2224.798849 Earth masses and a period of 308 days.

Among the listed planets, HD 160691 d has the shortest year by reported estimates, at 9.64 days, and HD 160691 c has the longest, at 3950 days. HD 160691 e has the second-shortest year, at 308 days, and HD 160691 b has the second-longest, at 645 days.