Otto Robert Frisch

Nuclear fission – the physical process by which very large atoms like uranium split into pairs of smaller atoms – is what makes nuclear bombs and nuclear power plants possible. But for many years, physicists believed it energetically impossible for atoms as large as uranium (atomic mass = 235 or 238) to be split into two.

Extract Lise Meitner’s name has become widely known for her part in the discovery of nuclear fission, which made atomic power possible, as well as atomic weapons. But among physicists she had been known for many years as one of the early pioneers in the study of radioactivity.