K2-155d

K2-155d is a super-Earth exoplanet orbiting the star K2-155, a cool M-dwarf located approximately 200 light-years away in the constellation Taurus. It was discovered by the Kepler space telescope's K2 mission, using the transit method, where the planet's passage in front of its host star causes a slight dimming of the star's light.

K2-155d is estimated to be roughly 1.6 times the size of Earth and has about 2.9 times the mass of Earth. Its orbital period is approximately 40 days. The exoplanet orbits within the habitable zone of its star, meaning it receives a similar amount of radiation as Earth receives from the Sun. This placement suggests that liquid water could potentially exist on its surface, although the actual habitability of K2-155d depends on various factors, including its atmosphere, albedo, and the activity of its host star.

The discovery and characterization of K2-155d are significant because it's one of the few known potentially habitable super-Earths orbiting a nearby star. This proximity makes it a prime target for future studies aimed at determining its atmospheric composition and searching for biosignatures, using powerful telescopes like the James Webb Space Telescope. Understanding the properties of K2-155d can provide valuable insights into the prevalence of potentially habitable worlds around M-dwarf stars and the prospects for life beyond Earth.