About this world
HD 41004 B b is a gas giant orbiting HD 41004 B, a cool red dwarf (type M2V) 136 light-years from Earth. It is about 1.1 times the size of Jupiter (its size estimated from its mass), with at least 18 Jupiter masses (a minimum, measured by radial velocity). It completes an orbit every 1.33 days at 0.017 AU from its star, closer than Mercury is to the Sun.
Its equilibrium temperature is about 1,879 K (1,606 °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 2003 by radial velocity with La Silla Observatory. The star wobbles toward and away from us, Doppler-shifting its spectrum.