The New Zealand born physicist Sir Ernest Rutherford (1871-1937, right) seen in the Cavendish Laboratory at Cambridge University. Rutherford became director of this laboratory in 1919 and in the same year he announced one of his major discoveries. He showed that the structure of an atom could be changed (nuclear transmutation) by bombarding it with alpha particles. He was also involved (1934) in the first nuclear fusion reaction in which tritium was the end product of deuterium nuclei collisions. He is considered to be the father of nuclear physics and in 1908 he was awarded the Nobel Prize for chemistry.