# A transiting super-Earth close to the inner edge of the habitable zone of an M0 dwarf star

## TL;DR

This paper reports the discovery of a super-Earth near the inner edge of the habitable zone around an M0 dwarf star, with detailed characterization of its properties and potential for follow-up studies.

## Contribution

The paper presents the detection and characterization of a super-Earth orbiting close to the habitable zone of an M0 dwarf star using K2 data, highlighting its suitability for future mass and atmosphere measurements.

## Key findings

- Super-Earth radius of 2.1±0.2 R⊕ near the radius gap.
- Equilibrium temperature of approximately 347 K.
- Radial velocity semi-amplitude estimated at ~1.9 m/s.

## Abstract

We present a super-Earth orbiting close to the inner edge of the habitable zone of the cool dwarf star K2-286 (EPIC 249889081), detected with data from the K2 mission in its $15^{th}$ campaign. The planet has radius of $2.1\pm0.2$ R$_{\oplus}$, near the 1.5 - 2.0 R$_{\oplus}$ gap in the radii distribution. The equilibrium temperature is $347^{+21}_{-11}$ K, cooler than most of the small planets with well measured masses, and the orbital period is $27.359\pm0.005$ days. K2-286, located at a distance of $76.3\pm0.3$ pc, is an M0V star with estimated effective temperature of $3926\pm100$ K, less active than other M dwarf stars hosting exoplanets. The expected radial velocity semi-amplitude induced by the planet on the star is $1.9^{+1.3}_{-1.2}$ m$\cdot$s$^{-1}$, and the amplitude of signals in transit transmission spectroscopy is estimated at $5.0\pm3.0$ ppm. Follow-up observations for mass measurements and transit spectroscopy should be desirable for this relatively bright target ($m_V=12.76, m_{Ks}=9.32$) hosting a transiting super-Earth within the inner edge of the habitable zone.