About this world
HD 240210 b is a gas giant orbiting HD 240210, a giant star (type K3III) 1.21 thousand light-years from Earth. It is about 1.1 times the size of Jupiter (its size estimated from its mass), with at least 5.2 Jupiter masses (a minimum, measured by radial velocity). It completes an orbit every 502 days at 1.2 AU from its star.
Its equilibrium temperature is about 971 K (698 °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 2009 by radial velocity with McDonald Observatory. The star wobbles toward and away from us, Doppler-shifting its spectrum.