|1934 and the discovery of artificial radioisotopes|
Most of radioactive nuclei have vanished from earth, but some have been recreated by man. In the beginning of 1934, Irène and Frédéric Joliot-Curie produced in their laboratory a radioactive atom of phosphorus which didn’t exist in nature by bombarding a sheet of aluminium by alpha particles. This phosphorus atom disintegrated like a natural radioactive element. Because of its numerous applications, particularly medical, the discovery of artificial radioactivity had an enormous impact. Its importance was quickly recognized. In 1935, Irène and Frédéric Joliot-Curie were awarded the Nobel Prize.