The HD 191939 system contains 5 exoplanets. It is located 174.85 light years away from the solar system.
| Mass | 0.81 solar masses |
| Radius | 0.94 solar radiae |
| Temperature | 5348 kelvin |
| Stellar Metallicity | -0.15 decimal exponent |
| Age | 8.7 billion years |
At more than 10 Earth masses, HD 191939 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 | 10.400 Earth masses |
| Density | 1.500 grams per cubic centimeter |
| Radius | 3.390 Earth radiae |
| Semi-major Axis | 0.078 AU |
| Eccentricity | 0 |
| Orbital Period | 8.880 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 | 2020-09 |
| Reference | Badenas-Agusti et al. 2020 |
At more than 10 Earth masses, HD 191939 c 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 | 7.200 Earth masses |
| Density | 1.400 grams per cubic centimeter |
| Radius | 3.080 Earth radiae |
| Semi-major Axis | 0.17 AU |
| Eccentricity | 0 |
| Orbital Period | 28.581 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 | 2020-09 |
| Reference | Badenas-Agusti et al. 2020 |
At more than 10 Earth masses, HD 191939 d 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 | 5.800 Earth masses |
| Density | 0.500 grams per cubic centimeter |
| Radius | 3.040 Earth radiae |
| Semi-major Axis | 0.207 AU |
| Eccentricity | 0 |
| Orbital Period | 38.352 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 | 2020-09 |
| Reference | Badenas-Agusti et al. 2020 |
At more than 50 Earth masses, HD 191939 e is a gas giant, a planet whose mass is mostly made up of hydrogen and helium, like Jupiter and Saturn.
| Mass | 108.000 Earth masses |
| Density | 0.290 grams per cubic centimeter |
| Radius | 12.700 Earth radiae |
| Semi-major Axis | 0.397 AU |
| Eccentricity | 0 |
| Orbital Period | 101.500 days |
| Discovery Method | Radial Velocity |
| Discovery Facility | W. M. Keck Observatory |
| Discovery Telescope | 10 m Keck I Telescope |
| Discovery Instrument | HIRES Spectrometer |
| Discovery Date | 2022-02 |
| Reference | Lubin et al. 2022 |
At more than 50 Earth masses, HD 191939 f is a gas giant, a planet whose mass is mostly made up of hydrogen and helium, like Jupiter and Saturn.
| Mass | 2065.000 Earth masses |
| Density | 5.540 grams per cubic centimeter |
| Radius | 12.700 Earth radiae |
| Semi-major Axis | 4.8 AU |
| Eccentricity | 0 |
| Orbital Period | 4450.000 days |
| Discovery Method | Radial Velocity |
| Discovery Facility | W. M. Keck Observatory |
| Discovery Telescope | 10 m Keck I Telescope |
| Discovery Instrument | HIRES Spectrometer |
| Discovery Date | 2022-02 |
| Reference | Lubin et al. 2022 |