About this world
Kepler-39 b is a gas giant orbiting Kepler-39, a yellow-white F-type star (type F7V) 3.45 thousand light-years from Earth. It is about 1.2 times the size of Jupiter and holds 20 Jupiter masses. It completes an orbit every 21.1 days at 0.16 AU from its star, closer than Mercury is to the Sun.
Its equilibrium temperature is about 897 K (624 °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 2011 by transit with Kepler. A planet crosses its star and dims it by a tiny, periodic fraction.