Who was Lise Meitner?
The physicist who, with Otto Frisch, worked out the theoretical explanation for nuclear fission and gave it its name — and who was then excluded from the Nobel Prize awarded for the discovery, in what is widely regarded as one of the clearest injustices in the history of the prize.
Her career before the discovery. Born in Vienna in 1878, she was among the first women to receive a physics doctorate there, then worked in Berlin, initially unpaid and confined to a basement workshop because women were not permitted in the main laboratory. She built a long and productive partnership with the chemist Otto Hahn, lasting some thirty years, and became a professor and a respected figure in European physics.
What happened in 1938. Being of Jewish descent, Meitner was forced to flee Nazi Germany, escaping to Sweden with almost nothing — her Austrian citizenship had ceased to protect her after the Anschluss.
The discovery itself. From exile she continued corresponding with Hahn, who reported a baffling experimental result: bombarding uranium with neutrons appeared to produce barium, a much lighter element, which made no sense under existing theory.
Meitner and her nephew Otto Frisch worked out why, over a walk in the snow at Christmas: the nucleus had split, and applying Einstein's mass-energy relation to the missing mass accounted exactly for the enormous energy released. They named the process fission, borrowing the term from biology, and published the explanation.
The prize. The 1944 Nobel Prize in Chemistry went to Otto Hahn alone. Archival study of the nomination records has attributed the exclusion to a combination of disciplinary boundaries between chemistry and physics, the committee's limited grasp of the theoretical contribution, wartime isolation, and bias.
What she did afterwards. She refused to work on the atomic bomb, declining an invitation to Los Alamos, and spoke about the moral responsibility of scientists.
Element 109 is named meitnerium in her honour.