Lise Meitner (7 November 1878 – 27 October 1968) was an Austrian-Swedish physicist who worked on radioactivity and nuclear physics. Meitner, Otto Hahn, and Otto Robert Frisch led the small group of scientists who first discovered nuclear fission of uranium when it absorbed an extra neutron; the results were published in early 1939. Meitner, Hahn and Frisch understood that the fission process, which splits the atomic nucleus of uranium into two smaller nuclei, must be accompanied by an enormous release of energy. Their research into nuclear fission helped to pioneer nuclear reactors to generate electricity as well as the development of nuclear weapons during World War II.
Otto Hahn and Lise Meitner carried out atomic experiments in Germany in the 1930s, finalizing their report in 1938-1939. While kept out of public journals by heavy security, news of the experiments managed to leak out, eventually coming to the attention of Albert Einstein in America. Einstein kept this knowledge to himself and did not share it with anyone high in the U.S. government, as he feared that PresidentJoe Steele would misuse the atomic bomb and destroy the world. U.S. Navy officer Hyman Rickover had also heard of the Hahn-Meitner experiments, and was able to assemble the team that eventually built the bomb for America.