![]() Some people were skeptical that neutron bombardment could produce transuranium elements, including Irene Joliot-Curie - Marie Curie’s daughter - and Meitner. These captured neutrons were then converted into positively charged protons and thus transformed the uranium into the incrementally larger elements on the periodic table of elements - the so-called “ transuranium,” or beyond uranium, elements. When scientists bombarded uranium with neutrons, they believed the uranium nucleus, rather than splitting, captured some neutrons. Meitner went further to explain how her scientific colleagues had gotten it wrong. Meisner remarked: “The whole ‘fission’ process can thus be described in an essentially classical way.” Just that simple, right? The lack of sufficient nuclear surface tension would then allow the nucleus to split into two fragments when struck by a neutron - a chargeless subatomic particle - with each fragment carrying away very high levels of kinetic energy. She noted that the surface tension of an atomic nucleus weakens as the charge of the nucleus increases, and could even approach zero tension if the nuclear charge was very high, as is the case for uranium (charge = 92+). Meitner based her fission argument on the “ liquid droplet model” of nuclear structure - a model that likened the forces that hold the atomic nucleus together to the surface tension that gives a water droplet its structure. She was excluded from the victory celebration because she was a Jewish woman. It was a massive leap forward in nuclear physics, but today Lise Meitner remains obscure and largely forgotten. In that letter, physicist Lise Meitner, with the assistance of her young nephew Otto Frisch, provided a physical explanation of how nuclear fission could happen. 11, 1939, with a letter to the editor of Nature - a premier international scientific journal - that described exactly how such a thing could occur and even named it fission. 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. 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.
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