| HD 102117 b / Leklsullun | |
| Discoverer: | Tinney et al. |
| Discovery Site: | Anglo-Australian Observatory, Australia |
| Discovered: | September 16, 2004 |
| Discovery Method: | Radial Velocity |
| Apsis: | astron |
| Aphelion: | 0.1717AU |
| Perihelion: | 0.1347AU |
| Semimajor: | 0.1532± |
| Eccentricity: | 0.106 ± 0.07 |
| Period: | 20.8133 ± 0.0064 d |
| Avg Speed: | 80.35 |
| Time Periastron: | 10942.9 ± 3 2.400.000 |
| Arg Peri: | 283 ± 3 |
| Semi-Amplitude: | 11.8 ± 0.77 |
| Star: | HD 102117 |
| Mass: | >0.172 ± 0.018 (>54.7) |
HD 102117 b, formally named Leklsullun,[1] is a planet that orbits the star HD 102117. The planet is a small gas giant a fifth the size of Jupiter. It orbits very close to its star, but not in a "torch orbit" like the famous 51 Pegasi b. It was one of the smallest extrasolar planets discovered as of 2006.
In 2004, the Anglo-Australian Planet Search announced a planet orbiting the star HD 102117. A short time later the HARPS team also announced the presence of a planet around this same star HD 102117. Both groups detected this planet using the radial velocity method.