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How did the Manhattan Project develop the atomic bombs used against Japan?

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Atomic bombing of Hiroshima — atomic bombings of Hiroshima and Nagasaki A gigantic mushroom cloud rising above Hiroshima, Japan, on August 6, 1945, after a U.S. aircraft dropped an atomic bomb on the city, immediately killing more than 70,000 people.

The Manhattan Project was a massive, top-secret U.S. government effort to develop the first atomic bomb during World War II. Under the leadership of General Leslie Groves and scientific director J. Robert Oppenheimer, the project operated across several key sites to pursue different production methods simultaneously.1234

Research and production were decentralized for security and efficiency:
* Oak Ridge: Focused on separating fissionable uranium-235 from uranium-238.14
* Hanford Engineer Works: Dedicated to the production of plutonium.14
* Los Alamos: Served as the primary laboratory for weapon design and development.34

Scientists at Los Alamos developed two primary bomb designs. The "gun-type" design, used for the uranium-based Little Boy, fired one piece of uranium at another to achieve critical mass. The "implosion-type" design, used for the plutonium-based Fat Man, utilized high explosives to compress a plutonium core into a supercritical state. Following the successful Trinity test on July 16, 1945, these weapons were deployed against Japan in August 1945.513