Habitable zones for earth-like planets around main sequence stars

Abstract

As stars evolve and brighten, the radial zone within which liquid water can exist at the surface of an Earth-like planet expands outward. Using a new planetary climate model we have calculated the evolution of these habitable zones around several main sequence stars of masses between 0.50 and 1.25 solar masses. This evolution is presented in the form of a habitability continuum diagram for each star. We also give results for post main sequence evolution of the habitable zone around a 1.0 M⋅ star. The inner radius of the habitable zone is determined by the moist greenhouse effect and the outer radius is taken to be the distance at which a dense CO2 atmosphere begins to condense. Preliminary results indicate that the range of planetary radii for which liquid water can exist for > 4.5 Byr is considerably broader than previously calculated.