The WASP-138 system contains 1 exoplanet. It is located 1351.05 light years away from the solar system.
| Mass | 1.22 solar masses |
| Radius | 1.36 solar radiae |
| Temperature | 6272 kelvin |
| Stellar Metallicity | -0.09 decimal exponent |
| Age | 3.44 billion years |
At more than 50 Earth masses, WASP-138 b is a gas giant, a planet whose mass is mostly made up of hydrogen and helium, like Jupiter and Saturn.
| Mass | 387.753 Earth masses |
| Density | 1.200 grams per cubic centimeter |
| Radius | 12.218 Earth radiae |
| Semi-major Axis | 0.0494 AU |
| Eccentricity | NaN |
| Orbital Period | 3.634 days |
| Discovery Method | Transit |
| Discovery Facility | SuperWASP |
| Discovery Telescope | Canon 200mm f/1.8L |
| Discovery Instrument | iKon-L CCD Camera |
| Discovery Date | 2017-03 |
| Reference | Lam et al. 2017 |