Rocket launches and re-entries of reusable and discarded objects inject familiar and exotic anthropogenic gases and aerosols to all layers of the atmosphere. The space sector is the only anthropogenic source that releases these gases and aerosols directly to the middle and upper layers of the atmosphere. Once emitted to these layers, pollutants may persist for years or decades, leaving a long legacy of atmospheric pollution. These pollutants are increasingly ubiquitous due to recent exponential space sector growth, yet there are no regulatory controls to mitigate harm. Quantification of the complex risks to the atmosphere is hindered by many uncertainties and data gaps, such as the chemical composition of exhaust from novel propellants, the locations and trajectories of ablative re-entry, the radiative properties of pollutants, the material composition of objects ablating on re-entry, and the physical and chemical evolution of chemicals released during re-entry. Lack of openly-available modelling tools is compounded by a scarcity of real-world experiments and ambient observations, and expected massive growth of space launches and, consequently, re-entries. This session invites submissions across all geophysical and related disciplines in and beyond academia to share planned, ongoing, or recently completed research that provides new knowledge in this area, explores new open-source modelling techniques, or exposes methodological gaps that need to be resolved to inform sustainability initiatives and global regulation. We are also interested in innovative and interdisciplinary approaches adopted by researchers in other domains that could be applied to advance understanding of environmental harm from the space sector. These include related topics such as geoengineering, space weather, space engineering, upper atmosphere circulation and chemistry, meteoritics, stratospheric aerosols and space debris management.