Looking for Signs of Life on Distant Planets Just Got Easier

"Although H2O signatures have been detected in the atmospheres of hot Jupiters, detecting molecular signatures, including H2O, on temperate terrestrial planets is exceedingly challenging, because of the small planetary radius and the small scale height (due to the lower temperature and presumably larger mean molecular weight)."

“Using a model that more realistically simulates atmospheric conditions, we discovered a new process that controls the habitability of exoplanets and will guide us in identifying candidates for further study... We found an important role for the type of radiation a star emits and the effect it has on the atmospheric circulation of an exoplanet in making the moist greenhouse state."

“As long as we know the temperature of the star, we can estimate whether planets close to their stars have the potential to be in the moist greenhouse state. Current technology will be pushed to the limit to detect small amounts of water vapor in an exoplanet’s atmosphere. If there is enough water to be detected, it probably means that planet is in the moist greenhouse state.”