What role did Enrico Fermi play in the Manhattan Project?

Enrico Fermi was a pivotal figure in the Manhattan Project, known primarily for his contributions to the development of the first nuclear reactor and advancing the understanding of nuclear fission. His most significant achievement was creating the first controlled nuclear chain reaction in December 1942 at the University of Chicago. This experiment demonstrated the practicality of using nuclear fission as a powerful energy source, which laid the groundwork for the development of atomic bombs.

While Fermi did not actually "split the atom" in the sense of being the first to discover nuclear fission—that credit generally goes to Lise Meitner and Otto Hahn—his work was crucial in understanding how to harness this process for the Manhattan Project. His expertise in physics and contributions to theoretical and experimental aspects of nuclear science made him a critical asset to the project's success.

In contrast, others involved in the project filled roles that focused on management, design, and military operations, but Fermi's unique scientific insights directly impacted the project’s advancement from theory to practical application.