Exoplanets are born and evolve in the radiation and particle environment created by their host star. The host star …’s optical and infrared radiation heats the exoplanet’s lower atmosphere and surface, while the ultraviolet, extreme ultraviolet … and X-radiation control the photochemistry and mass loss from the exoplanet’s upper atmosphere. Stellar radiation …

An Aquatic Habitability Index is proposed, based on Quantitative Habitability Theory, and considering a very general … model for life. It is a primary habitability index, measuring habitability for phytoplankton in the first place. The index … is applied to some case studies, such as the habitability changes in Earth due to environmental perturbations caused by …