The K2-166 Exoplanetary System
K2-166 is a star with 1.07 times the mass of the Sun, and 1.078 times its radius. It is located 1568.81 light years away from the solar system.
K2-166 is known to have 2 exoplanets in orbit around it.
K2-166 b was discovered by the K2 observatory using the transit method. Its discovery was announced in 2018-02. Its semi-major axis is 0.09 astronomical units, as compared to Earth's which is 1 astronomical unit. It takes 8.53 Earth days to complete an orbit around its host star, K2-166.
The mass of K2-166 b is 6.28 times the mass of Earth. The radius of K2-166 b is 2.19 that of Earth. At 6.28 Earth masses, K2-166 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. No Super Earths are known to exist in our solar system, but if it exists, the so-called Planet Nine could very well be a super Earth, as it is hypothesized to have a mass between five and ten Earth masses.