TP8

Understanding why planetary atmospheres look the way they do today - and reconstructing the evolutionary pathways that brought them to their present states - is one of the most compelling questions in modern planetary science. This session adopts a comparative planetology perspective, bridging solar system bodies and exoplanet populations through the lens of atmospheric evolution, investigated through observations, modelling, and mission-driven science.
Space missions have delivered a wealth of observations of the atmospheres and aeronomy of rocky planets and moons, from the lower atmosphere to regions interacting directly with the solar wind. With recent advances and forthcoming missions, planetary atmospheric science is entering a particularly active phase. This session invites contributions on the physical and chemical processes shaping the lower, middle, and upper atmospheres of terrestrial bodies in the Solar System and beyond, including atmospheric chemistry, energetics, dynamics, electrodynamics, atmospheric escape, surface–atmosphere interactions, and coupling with the space environment. We welcome studies based on spacecrafts (e.g., Messenger, BepiColombo, Venus Express, Akatsuki, EnVision, Davinci, Mars Express, MRO, TGO, EMM, MAVEN, MMX, among others), ground-based observations, numerical modelling, and laboratory experiments.
We welcome contributions addressing the long-term evolution of atmospheres across all planetary types. In the inner solar system, Venus and Mars stand as striking cases of evolutionary divergence from Earth. In view of upcoming ESA and NASA Venus missions, contributions addressing current understanding, open questions, and preparatory studies of the Venus atmosphere and its long-term history are particularly encouraged, from photochemistry and cloud dynamics to the transformative science expected from ESA's EnVision (and its VenSpec suite) and DAVINCI.
In the outer solar system, Titan's organic-rich and seasonally evolving atmosphere offers a unique window into photochemical complexity and long-term change, with new observational and modelling efforts building on the Cassini legacy. The gas and ice giants - characterized with unprecedented detail by JWST, Juno, and the forthcoming JUICE mission - further enrich this comparative picture; ice giant atmospheres in particular represent a frontier for solar system science and an archetype for the most abundant planetary class in the galaxy, with the scientific case for a Uranus mission gaining momentum under NASA's Decadal Survey and ESA's Voyage 2050 framework.
Finally, broader comparative studies linking solar system atmospheric structure and chemistry to the growing population of exoplanets accessible to spectroscopic characterization are warmly welcomed. This includes contributions on atmospheric escape and its demographic imprints on exoplanet populations - from the radius valley and the Neptune desert to observations of young systems caught in the act of losing their envelopes. Both observational and modelling contributions are welcome, as well as cross-disciplinary studies connecting solar system and exoplanet atmospheric science through laboratory measurements, modeling and/or observations.
The session will include solicited and contributed oral presentations, as well as posters.