About this world
HD 178911 B b is a gas giant orbiting HD 178911 B, a yellow, Sun-like star (type G5) 134 light-years from Earth. It is about 1.1 times the size of Jupiter (its size estimated from its mass), with at least 8 Jupiter masses (a minimum, measured by radial velocity). It completes an orbit every 71.5 days at 0.34 AU from its star, closer than Mercury is to the Sun.
Its equilibrium temperature is about 480 K (207 °C): far too hot for liquid water on its surface. At its size it almost certainly keeps a deep envelope of hydrogen and helium.
It was discovered in 2001 by radial velocity with W. M. Keck Observatory. The star wobbles toward and away from us, Doppler-shifting its spectrum.