About this world
HAT-P-13 c is a gas giant orbiting HAT-P-13, a yellow, Sun-like star (type G4) 805 light-years from Earth. It is about 1.1 times the size of Jupiter (its size estimated from its mass), with at least 14 Jupiter masses (a minimum, measured by radial velocity). It completes an orbit every 446 days at 1.3 AU from its star, on a strongly elongated orbit (e = 0.66).
Its equilibrium temperature is about 340 K (67 °C), which places it in the optimistic 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 2009 by radial velocity with W. M. Keck Observatory. The star wobbles toward and away from us, Doppler-shifting its spectrum. HAT-P-13 has 2 known planets; the others are HAT-P-13 b.