About this world
HD 221287 b is a gas giant orbiting HD 221287, a yellow-white F-type star (type F7V) 182 light-years from Earth. It is about 1.2 times the size of Jupiter (its size estimated from its mass), with at least 3.1 Jupiter masses (a minimum, measured by radial velocity). It completes an orbit every 456 days at 1.3 AU from its star.
Its equilibrium temperature is about 290 K (17 °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 2007 by radial velocity with La Silla Observatory. The star wobbles toward and away from us, Doppler-shifting its spectrum.