About this world
HD 43691 b is a gas giant orbiting HD 43691, a yellow, Sun-like star (type G0) 279 light-years from Earth. It is about 1.2 times the size of Jupiter (its size estimated from its mass), with at least 2.6 Jupiter masses (a minimum, measured by radial velocity). It completes an orbit every 37 days at 0.24 AU from its star, closer than Mercury is to the Sun.
Its equilibrium temperature is about 762 K (489 °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 2007 by radial velocity with Haute-Provence Observatory. The star wobbles toward and away from us, Doppler-shifting its spectrum.