About this world
HD 109286 b is a gas giant orbiting HD 109286, a yellow, Sun-like star (type G4V) 181 light-years from Earth. It is about 1.2 times the size of Jupiter (its size estimated from its mass), with at least 3 Jupiter masses (a minimum, measured by radial velocity). It completes an orbit every 520 days at 1.3 AU from its star, on a strongly elongated orbit (e = 0.34).
Its equilibrium temperature is about 259 K (−14 °C), which places it in the conservative habitable zone: the band where liquid water could exist on a rocky surface. At its size it almost certainly keeps a deep envelope of hydrogen and helium.
It was discovered in 2021 by radial velocity with Haute-Provence Observatory. The star wobbles toward and away from us, Doppler-shifting its spectrum.