The Exosphere as a Boundary: Origin and Evolution of Airless Bodies in the Inner Solar System and Beyond Including Planets with Silicate Atmospheres

In this review we discuss all the relevant solar/stellar radiation and plasma parameters and processes that act together in the formation and modification of atmospheres and exospheres that consist of surface-related minerals. Magma ocean degassed silicate atmospheres or thin gaseous envelopes from planetary building blocks, airless bodies in the inner Solar System, and close-in magmatic rocky exoplanets such as CoRot-7b, HD 219134 b and 55 Cnc e are addressed. The depletion and fractionation of elements from planetary embryos, which act as the building blocks for proto-planets are also discussed. In this context the formation processes of the Moon and Mercury are briefly reviewed. The Lunar surface modification since its origin by micrometeoroids, plasma sputtering, plasma impingement as well as chemical surface alteration and the search of particles from the early Earth's atmosphere that were collected by the Moon on its surface are also discussed. Finally, we address important questions on what can be learned from the study of Mercury's environment and its solar wind interaction by MESSENGER and BepiColombo in comparison with the expected observations at exo-Mercurys by future space-observatories such as the JWST or ARIEL and ground-based telescopes and instruments like SPHERE and ESPRESSO on the VLT, and vice versa.

Automated summary

This review discusses the various solar/stellar radiation and plasma parameters and processes that contribute to the formation and modification of atmospheres and exospheres composed of surface-related minerals. It covers topics such as magma ocean degassed silicate atmospheres, airless bodies in the inner Solar System, and rocky exoplanets with volcanic activity. It also explores the depletion and fractionation of elements from planetary embryos, the formation of the Moon and Mercury, and the surface modification of the Moon. Furthermore, it addresses the importance of studying Mercury's environment and solar wind interaction for understanding exo-Mercurys and highlights the relevance of future space observatories and ground-based telescopes for this research.