About this world
HD 204313 b is a gas giant orbiting HD 204313, a yellow, Sun-like star (type G5V) 156 light-years from Earth. It is about 1.2 times the size of Jupiter (its size estimated from its mass) and holds 4.6 Jupiter masses. It completes an orbit every 5.59 years at 3.2 AU from its star.
Its equilibrium temperature is about 163 K (−110 °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 2010 by radial velocity with La Silla Observatory. The star wobbles toward and away from us, Doppler-shifting its spectrum. HD 204313 has 3 known planets; the others are HD 204313 c and HD 204313 e.