The radius is approximately 2.6 times that of Earth, about 16,300 kilometers

Kepler-47c orbits a binary star system located about 3,340 light-years away from Earth in the constellation Cygnus.

Kepler-47c likely lacks a solid surface, consisting instead of a thick atmosphere of hydrogen and helium. Its conditions may be extreme, featuring high pressure and complex weather patterns, including storms and high-speed winds.

Kepler-47c is believed to have a dense core surrounded by a thick layer of gases. The core may consist of heavier elements, while the outer layers could be dominated by lighter gases. The exact composition and layering remain uncertain and are subjects of ongoing research. 

Unique for being part of a multi-planet system around a binary star, challenging assumptions about planetary stability and formation. Potential for habitable moons adds to its intrigue. 

Discovery Method: Transit Method

Year Discovered: 2012

Details: Kepler-47c was discovered as part of the Kepler mission, which utilized the transit method to monitor a binary star system for brightness dips. The analysis of light curves indicated multiple transiting planets, including Kepler-47c. Follow-up measurements confirmed its characteristics, making it one of the first planets identified in a multi-planet system around binary stars.