About this world
HD 216770 b is a gas giant orbiting HD 216770, a yellow, Sun-like star (type G9VCN+1) 120 light-years from Earth. It is about 1.3 times the size of Jupiter (its size estimated from its mass), with at least 0.57 Jupiter masses (a minimum, measured by radial velocity). It completes an orbit every 118 days at 0.46 AU from its star, on a strongly elongated orbit (e = 0.37).
Its equilibrium temperature is about 370 K (97 °C): too cold for liquid water on its surface. At its size it almost certainly keeps a deep envelope of hydrogen and helium.
It was discovered in 2003 by radial velocity with La Silla Observatory. The star wobbles toward and away from us, Doppler-shifting its spectrum.