The clever young people at the National ThinkTank who tackle an urgent societal problem each year include two Leiden alumni this autumn: Jiao Harmsen and Jort van Dalen. They will spend at least four months getting to grips with the topic of ‘education’.

What will happen if the lights in a large part of the city are switched off? How many stars can you see without all that light pollution? This is what researchers, artists and the residents of Leiden are going to investigate during Seeing Stars Leiden on 25 September. ‘Leiden is the ideal place for…