Who really discovered nuclear fission?

Nuclear fission involves splitting atoms into smaller parts, and releases a lot of energy.


After millennia of exploiting sources of chemical energy, such as wood, the discovery of nuclear fission in the 1930s gave humanity access to something far more potent: energy released by the splitting – ‘fission’ – of atomic nuclei.

Immediately recognised as the basis of a weapon of mass destruction, and now used to generate around 10 per cent of the world’s electricity, nuclear fission has always been controversial. Even its discovery provokes arguments.

What’s not in doubt is that nuclear fission was first achieved by a team led by the German chemist Otto Hahn in 1938. Along with his colleague Fritz Strassmann, Hahn found that uranium atoms could be split by bombarding them with neutrons. But baffled that mere subatomic particles could achieve this feat, Hahn contacted Lise Meitner, a former colleague and physicist based in Sweden. Together with fellow physicist Otto Frisch, she showed how fission really worked, and even gave the process its name.

Yet in 1944, the Nobel Committee awarded its chemistry prize solely to Hahn, ignoring the crucial insights of Meitner and Frisch. Historians now believe that, at the very least, Meitner should be regarded as the co-discoverer of nuclear fission, and suspect her contribution was overlooked in part because of her gender.

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