| HAT-P-13c | |
| Discoverer: | Bakos et al. |
| Discovery Site: |  United States |
| Discovered: | 21 July 2009 |
| Apsis: | astron |
| Aphelion: | 2.006AU |
| Perihelion: | 0.366AU |
| Semimajor: | 1.186 AU |
| Eccentricity: | 0.691 ± 0.018 |
| Period: | 428.5 ± 3 d 1.173 ± 0.008 y |
| Time Periastron: | 2454890.05 ± 0.48 |
| Arg Peri: | 176.7 ± 0.5 |
HAT-P-13c is a substellar object orbiting the star HAT-P-13 located 698 light years away from Earth in the constellation of Ursa Major. A search for transits was negative, however only 72% of the possible transit configurations could be ruled out. With a mass at least 15.2 times that of Jupiter, it may be a massive planet or a small brown dwarf. The gravitational effect of this object on the inner transiting planet HAT-P-13b may allow a precise determination of the inner planet's internal structure.[1]