Watch closely 🕵️ This is a cloud chamber. The wispy lines we can see appearing and then fading out are alpha and beta particles being emitted from the top of a box that Marie and Pierre Curie brought here to the Ri in 1903, which contained an early sample of radium. This demonstration visualizes the passage of ionizing radiation. Yes, the box is still radioactive today! ☢️ Here's how it works: Inside the chamber, you have a supersaturated vapour of water or alcohol. When the charged particles f

The cloud chamber shows the natural radiation in the atmosphere. ☢️ Peter Wothers shows how, when the charged alpha particles and smaller beta particles fire through its alcohol-heavy atmosphere, they cause little droplets to form, leaving cloud-like trails. ☁️ | Royal Institution of Great Britain