About this world
18 Del b is a gas giant orbiting 18 Del, a giant star (type G6III) 249 light-years from Earth. It is about 1.1 times the size of Jupiter (its size estimated from its mass), with at least 9.2 Jupiter masses (a minimum, measured by radial velocity). It completes an orbit every 2.69 years at 2.5 AU from its star.
Its equilibrium temperature is about 453 K (180 °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 2008 by radial velocity with Okayama Astrophysical Observatory. The star wobbles toward and away from us, Doppler-shifting its spectrum.