Rarefied Gas Dynamics

The 33rd International Symposium on Rarefied Gas Dynamics (RGD33) was held in Göttingen, Germany, from July 15 to 19, 2024.Since the first meeting in Nice in 1958, venues have changed every two years across countries and continents.This mark ed only the third time the RGD symposium was held in Germany, returning to Göttingen exactly 50 years after it was first hosted there.Rarefied gas dynamics is a branch of physics mainly concerned with the study of gas flows in which processes at the molecular level play a role.With its diverse applications ranging from astrophysics t o micro-flows, it continues to raise challenging questions that require a multidisciplinary effort of mathematicians, physicists, chemists, computer scientists and engineers.Still under the impression of the fading COVID-19 pandemic, the RGD33 symposium was deliberately planned as a purely face-to-face event in order to promote direct scientific exchange and strengthen the professional community.The response was overwhelmingly positive.With 243 participants from 30 countries, the attendance exceeded expectations.However, for the first time in its history, the symposium was severely affected by sanctions imposed on Russian uni versities and research institutions as well as numerous other organizations embargoed by the USA and the European Union.Nevertheless, we remain committed to global scientific cooperation, as we are convinced that it also plays an important role in strengthening civil society against authoritarianism worldwide.A total of 176 papers were presented in three parallel tracks.In addition, 49 posters were presented and put up for discussion in a dedicated session.The organizers took care to include a balance of contributions from mathematics, natural sciences and engineering in order to promote interdisciplinary exchange.Among the topics discussed during RGD33 were: Boltzmann and Related Equations, Granular Flow s, Gas-Surface Interactions, Quasi-Classical Trajectory S imulation, Moment Methods, v