On February 11, 1939, the journal Nature published a theoretical paper on nuclear fission. The term was coined by the authors Lise Meitner and Otto Fritsch, her nephew. They knew that when a uranium nucleus was struck by neutrons, barium was produced. Seeking an explanation, they used Bohr's "liquid drop" model of the nucleus to envision the neutron inducing oscillations in a uranium nucleus, which would occasionally stretch out into the shape of a dumbbell. Sometimes, the repulsive forces between the protons in the two bulbous ends would cause the narrow waist joining them to pinch off and leave two nuclei where before there had been one. They calculated the huge amounts of energy released. This was the basis for nuclear chain reaction and was recognized by the U.S. government as a potential weapon which led to the establishment of the Manhattan Project. Meitner was invited to work on the project but refused.
Books in our collection
Out of the shadows: contributions of twentieth-century women to physics by Nina Byers, Gary Williams
A devotion to their science: pioneer women of radioactivity by Marelene Rayner-Canham, Geoffrey Rayner-Canham