About this world
HD 31253 b is a gas giant orbiting HD 31253, a yellow-white F-type star (type F8) 190 light-years from Earth. It is about 1.3 times the size of Jupiter (its size estimated from its mass), with at least 0.62 Jupiter masses (a minimum, measured by radial velocity). It completes an orbit every 466 days at 1.3 AU from its star, on a strongly elongated orbit (e = 0.3).
Its equilibrium temperature is about 348 K (75 °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 W. M. Keck Observatory. The star wobbles toward and away from us, Doppler-shifting its spectrum.