About this world
HD 159243 b is a gas giant orbiting HD 159243, a yellow, Sun-like star (type G0V) 239 light-years from Earth. It is about 1.2 times the size of Jupiter (its size estimated from its mass), with at least 1.1 Jupiter masses (a minimum, measured by radial velocity). It completes an orbit every 12.6 days at 0.11 AU from its star, closer than Mercury is to the Sun.
Its equilibrium temperature is about 942 K (669 °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 2013 by radial velocity with Haute-Provence Observatory. The star wobbles toward and away from us, Doppler-shifting its spectrum. HD 159243 has 2 known planets; the others are HD 159243 c.