This session invites papers on the satellites of our Solar System which are active in terms of atmosphere and/or surface. These include : Titan, Enceladus, Io and Triton, but note that there is also an Enceladus-devoted session (GP3). Presentations should include results on the ever-evolving atmosphere of Titan, the ejecting water vapor atmosphere around Enceladus, the volcanic Io torus, and the nitrogen Triton envelope. But also all other aspects of these satellites (geological, geophysical, geochemical, biochemical, and meteorological) and their interaction with their environment, will be discussed, as well as how they are currently being explored and/or will be studied in the future.