Bonner sphere

A Bonner Sphere is a device used to measure the amount of radiation that is given off by radioactive materials. It consists of a hollow sphere, made of a special material like plastic or lead, and filled with lots of little detectors inside. When radioactive material is put near the Bonner Sphere, the detectors measure how much radiation is coming out. The Bonner Sphere helps scientists to measure the amount of radiation that is coming out of the material, so they can make sure it is safe to be around.