About this world
HD 29399 b is a gas giant orbiting HD 29399, a giant star (type K1III) 144 light-years from Earth. It is about 1.2 times the size of Jupiter (its size estimated from its mass), with at least 1.6 Jupiter masses (a minimum, measured by radial velocity). It completes an orbit every 2.44 years at 1.9 AU from its star.
Its equilibrium temperature is about 358 K (85 °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 2022 by radial velocity with La Silla Observatory. The star wobbles toward and away from us, Doppler-shifting its spectrum.