The HD 219666 system contains 1 exoplanet. It is located 307.15 light years away from the solar system.
| Mass | 0.92 solar masses |
| Radius | 1.03 solar radiae |
| Temperature | 5527 kelvin |
| Stellar Metallicity | 0.04 decimal exponent |
| Age | 10 billion years |
At more than 10 Earth masses, HD 219666 b is an ice giant, a planet that is made up mostly of volatiles like water, amonia and methane, and enveloped by a dense hydrogen and helium atmosphere, much like Uranus and Neptune.
| Mass | 16.600 Earth masses |
| Density | 0.870 grams per cubic centimeter |
| Radius | 4.710 Earth radiae |
| Semi-major Axis | 0.06356 AU |
| Eccentricity | 0 |
| Orbital Period | 6.036 days |
| Discovery Method | Transit |
| Discovery Facility | Transiting Exoplanet Survey Satellite (TESS) |
| Discovery Telescope | 0.1 m TESS Telescope |
| Discovery Instrument | TESS CCD Array |
| Discovery Date | 2019-03 |
| Reference | Esposito et al. 2019 |