Kepler-11c
| Size comparison of Kepler-11c (gray) with Neptune. | |
| Discovery | |
|---|---|
| Discovery date | 2 February 2011 | 
| Transit (Kepler Mission) | |
| Orbital characteristics | |
| .106 AU (15,900,000 km) | |
| 13.02502 d | |
| Inclination | 89 | 
| Star | Kepler-11 (KOI-157) | 
| Physical characteristics | |
| 3.15 (± .30) R🜨 | |
| Mass | 13.5+4.8 −6.1 M🜨 | 
| Mean density | 2.3 +1.3 −1.1 g cm−3 | 
| Temperature | 833 K (560 °C; 1,040 °F) | 
Kepler-11c is an exoplanet discovered in the orbit of the Sun-like star Kepler-11 by the Kepler space telescope, a NASA telescope aiming to discover Earth-like planets. It is the second planet from its star, and is most likely a water planet with a thin hydrogen–helium atmosphere. Kepler-11c orbits Kepler-11 every 10 days, and has an estimated density twice that of pure water. It is estimated to have a mass thirteen times that of Earth and a radius three times that of Earth. Kepler-11c and its five sister planets form the first discovered system with more than three transiting planets. The Kepler-11 system also holds the record of being the most compact and the flattest system discovered. Kepler-11c and the other Kepler-11 planets were announced to the public on February 2, 2011, and was published in Nature a day later.