The year is 1935 and Lise Meitner, Otto Hahn, and Fritz Strassmann are working tirelessly to understand which heavy natural elements change under neutron bombardment. Three years later, they had discovered around 10 different half-life activities of natural elements. Soon after, Hahn and Strassman discover 6 more. While bombarding these elements with neutrons, they were shocked at what happened. They found that during this process, the uranium nuclei had changed, and even broke into two roughly equal pieces! This uranium nuclei now became radioactive barium isotopes, half as heavy as uranium.
Since this was previously thought to be impossible, this process had to be replicated. Hahn sent a letter to Meitner, a Jewish woman who had to leave her research to stay safe from Nazis. When Meitner’s nephew, Otto Frisch, came to visit her, they began doing calculations together. Frisch was able to draw diagrams showing the process of a uranium nucleus splitting into two after being hit with a neutron. They made the math make sense, and couldn’t believe it! The news was soon shared with the science community in America. Frisch was the one who named this process “fission.”
Scientists quickly came on board with this process, realizing that if the fission reaction emitted secondary neutrons, it was possible to have a chain reaction occur, which releases large amounts of energy. This was a huge leap for the creation of the atomic bomb, and was a catalyst for the Manhattan Project.