The inner solar system has three rocky terrestrial planets with substantial atmospheres. Each one is unique and each of their atmospheres differs from every other in important ways, including their composition, isotopic and interior evolution. Many questions remain unanswered despite the long history of research on the solar system. For most of its history, the Earth has been habitable, but its atmosphere and geology have evolved tremendously. The Archean Earth was very different to the modern Earth, yet it was already habitable as early as 3.7 gigayears ago. How probable was it for the Earth to stay habitable for such a long geological time? Why did Mars lose most of its atmosphere? Its small mass certainly played a role, but what role has been played by the geological processes, for instance, volcanism and magnetic dynamo? Did Venus ever have habitable conditions? If so, how long did they last and why did they disappear?
In this session, we focus on several main topics relevant for formation of habitable conditions:
– The evolution of the composition of the atmospheres of Earth, Venus, and Mars, and the role played by volcanic outgassing and planetary dynamos;
– Influence of the atmospheric escape to space from upper atmospheres on surface conditions;
– Evolving climates and possible past habitability windows for Mars and Venus.
This session is dedicated to studies of the divergent evolution of the three planets and the role played by the Sun. We aim to provide a synergetic view of the evolution of the Earth, Venus, and Mars, with contributions on planetary interiors and magnetic dynamos, and atmospheres' formation and escape being equally welcome.