Kepler-9b
Size comparison of Kepler-9b (left) with Jupiter (right) | |
| Discovery | |
|---|---|
| Discovered by | Kepler Mission team |
| Discovery site | Kepler space telescope |
| Discovery date | 26 August 2010 |
| Transit | |
| Designations | |
| KOI-377.01 | |
| Orbital characteristics | |
| 0.140 ± 0.001 AU (20,940,000 ± 150,000 km) | |
| Eccentricity | 0 |
| 19.24 d | |
| Inclination | 88.55 |
| Star | Kepler-9 |
| Physical characteristics | |
| 0.842 ± 0.069 RJ | |
| Mass | 43.5+2.7 −3.3 M🜨 |
Mean density | 0.4±0.1 g cm−3 |
Kepler-9b is one of the first planets discovered outside the Solar System (exoplanets) by NASA's Kepler Mission. It revolves around the star Kepler-9 within the constellation Lyra. Kepler-9b is the largest of three planets detected in the Kepler system by transit method; its mass is roughly half that of the planet Saturn, and it is the largest planet in its system. Kepler-9b and Kepler-9c display a phenomenon called orbital resonance, in which gravitational pull from each planet alters and stabilizes the orbit of the other. The planet's discovery was announced on August 26, 2010.