K2-22b (also known as EPIC 201637175 b) is an exoplanet 801 ly from Earth, rapidly orbiting the red dwarf K2-22 with an orbital period of 9.145872 hours.[2] It has a mass of 0.02 ME and a radius below 0.71 ME.[3] The planet was not detected in the K2 photometry. K2 photometry reveals the presence of an anomalous light curve consistent with evaporation of dust from the planet. This dust forms a tail both ahead and behind the planet, similar to some comets in the Solar System.[1] The evaporation of this dust requires a low surface gravity from the host planet, implying it is a low mass, "Mars, Mercury, or even lunar sized bodies with surface gravities of 1/6 to 1/3 that of Earth are to be preferred."[1]
| Discovery[1] | |
|---|---|
| Discovery site | Kepler Space Observatory |
| Discovery date | 2015 |
| Transit | |
| Orbital characteristics | |
| 0.0088 AU (1,320,000 km) | |
| Eccentricity | null[2] |
| 0.381078[2] d | |
| Inclination | null[2] |
| Star | K2-22 |
| Physical characteristics | |
Mean radius | <0.71R🜨[3] |
| Mass | 0.02 ME[3] |
| Temperature | 2,100 K (1,830 °C; 3,320 °F) |
The survey in 2020 has failed to validate the existence of the planet, although did not claim it to be a false positive.[4]
The observation of planetary system in 2021 has failed to detect the planet itself, placing an upper limit of 0.71R🜨 on its size. With the observed mass loss rate, the probable planet mass is 0.02ME, and the planet will be gone in 21 million years in future.[3]
