Nuclear fuel rod, late 20th century.
© Science Museum / Science & Society Picture Library
Fuel rods have a key role in nuclear reactors. This rod contains pellets of a compound of uranium, uranium dioxide and a high proportion of uranium-235. The rods are fitted into the core of the reactor and help the proces of nuclear fision. Rods such as this are used in the Magnox reactor and the British Advanced Gas-cooled Reactor (AGR).