By measuring the dip in brightness when EPIC 201912552.01 transits in front of its host star, the size of the planet is estimated to be 2.24 ± 0.25 times the diameter of Earth. With such a size, EPIC 201912552.01 is too large to be a rocky planet like Earth. Instead, the planet is most probably a mini-Neptune. The equilibrium temperature of the planet is estimated to be 271 ± 16 K. Both the planet and its host star are located at a distance of approximately 110 light-years. The proximity and relative brightness of the system makes EPIC 201912552.01 a good target for its atmosphere to be characterised by future space-based telescopes such as the James Webb Space Telescope (JWST).
Montet et al. (2015), “Stellar and Planetary Properties of K2 Campaign 1 Candidates and Validation of 18 Systems, Including a Planet Receiving Earth-like Insolation”, arXiv:1503.07866 [astro-ph.EP]