The HAT-P-18 system contains 1 exoplanet. It is located 526.42 light years away from the solar system.
| Mass | 0.77 solar masses |
| Radius | 0.75 solar radiae |
| Temperature | 4803 kelvin |
| Stellar Metallicity | 0.1 decimal exponent |
| Age | 12.4 billion years |
At more than 50 Earth masses, HAT-P-18 b is a gas giant, a planet whose mass is mostly made up of hydrogen and helium, like Jupiter and Saturn.
| Mass | 62.610 Earth masses |
| Density | 0.250 grams per cubic centimeter |
| Radius | 11.153 Earth radiae |
| Semi-major Axis | 0.0559 AU |
| Eccentricity | 0.084 |
| Orbital Period | 5.508 days |
| Discovery Method | Transit |
| Discovery Facility | HATNet |
| Discovery Telescope | Canon 200mm f/1.8L |
| Discovery Instrument | 2K CCD Sensor |
| Discovery Date | 2011-01 |
| Reference | Hartman et al. 2011 |