‘The atom factories: making new elements’ explores the synthesis of new elements. The transmutation of new elements is only possible due to radioactivity. Rutherford discovered that bombarding nuclei with protons caused nuclear decay, and Fermi realised that neutron bombardment could create transuranic elements. Both processes released vast amounts of energy, harnessed by the United States in World War II. As well as being broken apart, nuclei can also be fused into heavier nuclei. This releases even more energy. This process occurs in the Sun, but is much harder to perform on Earth. As heavier and heavier elements have been found, arguments have raged about priority and naming rights.