About this world
HD 190984 b is a gas giant orbiting HD 190984, a yellow-white F-type star (type F8V) 483 light-years from Earth. It is about 1.2 times the size of Jupiter (its size estimated from its mass) and holds 3.6 Jupiter masses. It completes an orbit every 13.4 years at 5.5 AU from its star, on a strongly elongated orbit (e = 0.57).
Its equilibrium temperature is about 152 K (−121 °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 2009 by radial velocity with La Silla Observatory. The star wobbles toward and away from us, Doppler-shifting its spectrum.