Kepler-438

Kepler-438b is a near-Earth-sized exoplanet that was discovered orbiting within the habitable zone of its parent star. It has frequently been ranked among the most Earth-like exoplanets ever identified by the Kepler space mission.

Kepler-438 is a K-type star, which is slightly cooler and smaller than our own Sun, often referred to as an orange dwarf. These types of stars are highly favored in the search for extraterrestrial life due to their incredibly long, stable lifespans.

The star and its Earth-like planet are located roughly 470 light-years away from our solar system in the constellation Lyra. This means that current telescopes cannot directly image the planet, and we only know of its existence through transit photometry.

While it ranks high on the Earth Similarity Index, astronomers later discovered that Kepler-438 is a highly active flare star. These frequent, massive bursts of radiation likely stripped away the planet's atmosphere, drastically reducing its chances of actually hosting life.