Kepler 16 is a binary star system with an M-type dwarf and a K-type star orbiting their centre of mass with 0.22 astronomical units of separation. A planet has been detected orbiting both of them as if they were one. The planet, Kepler 16b, is a gas giant about one-third of the mass of Jupiter and about three-quarters of its radius. It orbits the binary star at a distance of 0.78 AU, taking 228 days to complete one revolution. This artist's impression imagines a double sunset seen on one of the (hypothetical) moons of the giant planet.