Kepler-186 f orbits a red dwarf M-type star 500 light-years away, boasting a radius of 1.2 × Earth. It completes an orbit every 130 days at 0.43 AU, positioning it in the habitable zone’s outer reaches for potential surface liquid water. As the pioneering Earth-sized world confirmed in such a zone, it provides key insights into rocky planet formation around cool stars. This timeless entry in the Galactic Codex marks a milestone in our quest to understand habitable environments beyond our solar system.
