The easiest way to smuggle nuclear bombs is in cargo containers. How can you detect them? How can you look inside nuclear waste drums and inspect active volcanoes from a safe distance? What is still standing inside the Fukushima power plant? Muon tomography is a novel imaging technology that allows imaging of the inside of closed objects without introducing radiation, from a safe distance. This makes it an excellent technique to probe the internal structure of active volcanoes, to detect nuclear bombs smuggled in cargo containers and monitor legacy nuclear waste. Dr Velthuis will explain how muon tomography works and how you can address the aforementioned topics.