The erosion of large primary atmospheres typically leaves behind substantial secondary atmospheres on temperate rocky planets.

ABSTRACT: Exoplanet exploration has revealed that many-perhaps most-terrestrial exoplanets formed with substantial H₂-rich envelopes, seemingly in contrast to solar system terrestrials, for which there is scant evidence of long-lived primary atmospheres. It is not known how a long-lived primary atmosphere might affect the subsequent habitability prospects of terrestrial exoplanets. Here, we present a new, self-consistent evolutionary model of the transition from primary to secondary atmospheres. The model incorporates all Fe-C-O-H-bearing species and simulates magma ocean solidification, radiative-convective climate, thermal escape, and mantle redox evolution. For our illustrative example TRAPPIST-1, our model strongly favors atmosphere retention for the habitable zone planet TRAPPIST-1e.

SUBMITTER: Krissansen-Totton J 

PROVIDER: S-EPMC11437211 | biostudies-literature | 2024 Sep

REPOSITORIES: biostudies-literature