Collisional processes are integral mechanisms that both shape the final configuration of the Solar System, and modify planetary surfaces and small bodies from its birth until today.
This session aims at understanding planetary impact processes at all scales, in terms of impact cratering and ejecta dynamics, crater distribution and crater chronology, material mixing, shock metamorphism and other geochemical consequences, ejecta-atmosphere interactions, impact induced climatic and environmental effects, and biotic responses.
We welcome oral and poster presentations across this broad range of studies about natural or artificial impact collision phenomena on planetary surfaces and small bodies. In particular, abstracts on impact modelling, impact laboratory experiments, geologic and structural mapping, petrographic and geochemical analysis of impact products, as well as remote sensing observations from space missions to planets and small bodies. We also welcome the examination of competing hypotheses for the giant impact formation of terrestrial and outer solar system bodies. Finally, we also support abstracts investigating the DART impact, whose outcome will be observed by HERA few months after this conference.

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.

Understanding surface–exosphere coupling is essential for interpreting observations of airless planets and planning future missions. This session focuses on the physical processes linking surface‑bounded exospheres to their parent surfaces, from atomistic interactions to global dynamics. We welcome contributions from data analysis, laboratory experiments, theoretical work, and numerical modelling that advance our understanding of these systems.

Topics include surface–volatile and plasma interactions, micrometeoroid bombardment, irradiation, space weathering, and volatile implantation. We particularly encourage studies that connect multiple processes or spatial and temporal scales, highlighting the two‑way coupling where surface properties influence exospheric behaviour and exospheric processes contribute to surface evolution.

Comparative studies across planetary bodies, including the Moon, Mercury, asteroids, and icy moons, are also welcome to help refine the physical framework governing surface–exosphere interactions. Contributions linking surface–exosphere processes to exoplanets with tenuous or escaping atmospheres are welcome. This session aims to build a coherent, multi‑scale perspective on the mechanisms shaping these environments and their evolution.

We particularly encourage early‑career scientists to submit abstracts for oral presentations.

Space environments, including magnetospheres, ionospheres, atmospheres, and associated auroral regions, are fundamental components of planetary and cometary systems. They are shaped by solar radiation and influenced by a wide range of processes such as space‑weather variability, solar wind dynamics, and changes in the neutral atmosphere. Within these systems, ionospheres play a central role in governing overall dynamics: they form the critical interface linking the neutral atmosphere, exosphere, and surrounding plasma environments (e.g., the solar wind at Mars, Venus, Pluto, and comets, or the Kronian magnetosphere at Titan). Understanding how each unmagnetized body responds to these external and internal drivers is essential for comparative aeronomy. While these bodies may share broadly similar behaviours, their distinct physical characteristics lead to scientifically significant differences, including in their auroral emissions and ionospheric responses.
This session focuses on the space environments, including auroral phenomena of Mars, Venus, Pluto, Titan, Jovian moons, comets, and related comparative studies, including analogies with the ionospheres of magnetized bodies. We invite abstracts addressing remote‑sensing and in‑situ observations, modelling efforts, instrumentation, and mission concepts.
Topics may include, but are not limited to: day‑ and night‑side ionospheric variability; sources and drivers of ionization; ion‑neutral interactions; current systems; comparative ionospheric and auroral studies across bodies; and solar‑wind–ionosphere coupling, including the response of neutral and ionized regimes to transient space‑weather events. Abstracts addressing general plasma processes and atmospheric escape are also welcome.

Planetary regoliths play a key role in shaping the evolution, mechanical response, and exploration of celestial bodies across the Solar System. Understanding the behaviour of regolith materials in varying gravitational, thermal, and atmospheric conditions is essential for interpreting surface processes, understanding planetary origin and evolution, and for supporting future robotic and human exploration.
This session focuses on the mechanical, geotechnical, dynamical (flow) and thermophysical properties of regolith on planetary bodies such as the Moon, Mars, asteroids, comets, and natural satellites. We welcome contributions based on laboratory experiments, numerical simulations, and theoretical analyses, in addition to studies using in-situ, remote sensing, or returned sample data and simulants.
The session aims to provide a forum for advancing our understanding of regolith physics across planetary environments and for enhancing connections between disciplines: planetary science, granular physics, and geotechnical engineering. Interdisciplinary approaches that bridge experiments, modelling, and observations are encouraged and we particularly encourage early career scientists to submit an abstract for an oral presentation.

Volcanism, tectonics, and seismicity represent key expressions of internal activity across the Solar System, fundamentally shaping the surfaces and interiors of terrestrial planets, moons, and icy satellites. Recent advances — including high-resolution orbital datasets, returned lunar samples, and seismic measurements from the Moon and Mars — have provided major insights into planetary interior structure, lithospheric processes, and the links between magmatism, tectonics, and seismic behavior. Together, these observations are transforming our understanding of how planetary bodies evolve and how endogenic processes manifest under different physical and environmental conditions.

Following the success of missions such as InSight, upcoming and recent missions — including Dragonfly, VERITAS, EnVision, Chang’e 6, and the Farside Seismic Suite — promise substantial progress in characterizing volcanic, tectonic, and seismic processes on Titan, Venus, and the Moon. These missions will refine constraints on planetary interiors, crustal structure, and the mechanisms driving seismicity. In parallel, small-body seismology is rapidly emerging as a new frontier, with future exploration concepts increasingly incorporating seismic investigations of asteroids and comets.

This session invites contributions addressing planetary volcanism, tectonics, and seismicity through observational, analytical, experimental, and theoretical approaches. We welcome studies of volcanic and tectonic landforms, magma–tectonic interactions, faulting and lithospheric deformation, seismicity and interior structure, as well as numerical and laboratory modeling. Submissions on geochemical and geophysical constraints, comparative planetology, mission concepts, instrumentation, and data analysis related to planetary interiors and seismic processes on planets and small bodies are particularly encouraged.

Sediment transport processes are fundamental for shaping the surfaces of rocky and icy bodies in the Solar System. These processes are varied; from mass-wasting on hillslopes, to the transport of sediment in water- and non-water-based systems, to aeolian processes across a wide range of surfaces and atmospheres. Much of the fundamentals of these processes remain poorly understood in the varying surface environments of the planetary bodies in our Solar System: from the mobility of landslides and debris flows on Mars, to the dynamics of deltas and fluvial systems on Mars and Titan, to aeolian bedform morphology and dynamics on Mars, Titan, Pluto, as well as asteroids and cometary bodies.

The aim of this session is to bring together researchers from different disciplines such as geomorphology and sedimentology to stimulate knowledge exchange based on the broad topic of sediment transport processes under varying planetary conditions, rather than one planetary environment.

We encourage contributions based on, but not limited to, mass-wasting processes (landslides and debris flows), sediment transport environments (rivers and deltas) on Earth, Mars, and Titan, and aeolian bedforms under different surface atmospheric interaction conditions (from rocky and icy planetary bodies to small solar system bodies). We welcome a broad range of approaches: remote sensing (geomorphological, geophysical and compositional analysis), laboratory experiments, numerical modelling, as well as analogue studies.