Kepler-11b
Kepler-11b is an exoplanet discovered around the star Kepler-11 by the Kepler spacecraft, a NASA-led mission to discover Earth-like planets. Kepler-11b is less than about three times as massive and twice as large as Earth, but it has a lower density (≤ 3 g/cm3), and is thus most likely not of Earth-like composition. Kepler-11b is the hottest of the six planets in the Kepler-11 system, and orbits more closely to Kepler-11 than the other planets in the system. Kepler-11b, along with its five counterparts, form the first discovered planetary system with more than three transiting planets—the most densely packed known planetary system. The system is also the flattest known planetary system. The discovery of this planet and its five sister planets was announced on February 2, 2011, after follow-up investigations.
Size comparison of Kepler-11b (gray) with Neptune and Earth. | |
| Discovery | |
|---|---|
| Discovered by | Kepler team |
| Discovery date | 2 February 2011 |
| Transit (Kepler Mission) | |
| Orbital characteristics | |
| .091 AU (13,600,000 km) | |
| 10.30375 d | |
| Inclination | 88.5 |
| Star | Kepler-11 (KOI-157) |
| Physical characteristics | |
Mean radius | 1.83+0.07 −0.04 R🜨 |
| Mass | 2.78+0.64 −0.66< ME |
Mean density | 4.5+1.3 −1.3 g cm−3 |
| Temperature | 900 K (627 °C; 1,160 °F) |