The Kepler-221 system contains 4 exoplanets. It is located 1256.45 light years away from the solar system.
| Mass | 0.82 solar masses |
| Radius | 0.82 solar radiae |
| Temperature | 5243 kelvin |
| Stellar Metallicity | 0.062 decimal exponent |
| Age | 4.57 billion years |
At 3.562 Earth masses, Kepler-221 b is a so called Super Earth. Super Earths could be terrestrial worlds like Earth, but they could also be ocean worlds or terrestrial worlds wrapped in a substantial atmosphere, in which case some refer to them as Mini Neptunes.
| Mass | 3.570 Earth masses |
| Density | 3.920 grams per cubic centimeter |
| Radius | 1.710 Earth radiae |
| Semi-major Axis | 0.037 AU |
| Eccentricity | 0 |
| Orbital Period | 2.796 days |
| Discovery Method | Transit |
| Discovery Facility | Kepler |
| Discovery Telescope | 0.95 m Kepler Telescope |
| Discovery Instrument | Kepler CCD Array |
| Discovery Date | 2014-03 |
| Reference | Rowe et al. 2014 |
At more than 10 Earth masses, Kepler-221 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 | 15.100 Earth masses |
| Density | 3.300 grams per cubic centimeter |
| Radius | 2.930 Earth radiae |
| Semi-major Axis | 0.059 AU |
| Eccentricity | 0 |
| Orbital Period | 5.691 days |
| Discovery Method | Transit |
| Discovery Facility | Kepler |
| Discovery Telescope | 0.95 m Kepler Telescope |
| Discovery Instrument | Kepler CCD Array |
| Discovery Date | 2014-03 |
| Reference | Rowe et al. 2014 |
At more than 10 Earth masses, Kepler-221 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 | 7.900 Earth masses |
| Density | 2.130 grams per cubic centimeter |
| Radius | 2.730 Earth radiae |
| Semi-major Axis | 0.087 AU |
| Eccentricity | 0 |
| Orbital Period | 10.042 days |
| Discovery Method | Transit |
| Discovery Facility | Kepler |
| Discovery Telescope | 0.95 m Kepler Telescope |
| Discovery Instrument | Kepler CCD Array |
| Discovery Date | 2014-03 |
| Reference | Rowe et al. 2014 |
At more than 10 Earth masses, Kepler-221 e 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 | 7.410 Earth masses |
| Density | 2.240 grams per cubic centimeter |
| Radius | 2.630 Earth radiae |
| Semi-major Axis | 0.13 AU |
| Eccentricity | 0 |
| Orbital Period | 18.370 days |
| Discovery Method | Transit |
| Discovery Facility | Kepler |
| Discovery Telescope | 0.95 m Kepler Telescope |
| Discovery Instrument | Kepler CCD Array |
| Discovery Date | 2014-03 |
| Reference | Rowe et al. 2014 |