General Physics Colloquium Wed. 7th January 15:15-16:00 Fys. Aud. Title: What can be the worst-case scenario for a solar particle storm and how often may we expect those? Speaker: Ilya Usoskin, Sodankylä Geophysical Observatory, University of Oulu, Finland Abstract: The era of direct observations of space weather is several decades old, and a number of strong solar particle storms has been observed. However, it remains an open question how strong such events can be and how often they appear. It is crucially important for the planning of future space missions to identify the worst case scenarios. Here, I provide an overview of the methods and results from studies of solar energetic particle events on millennial timescales using indirect proxies based on cosmogenic isotopes in terrestrial and lunar natural archives. Open attachment to place in calendar Wine and cheese will be served at 4pm