Nuclear fission Mexico, which was the scientific hub for research on bomb development and design. Other sites, notably the Berkeley Radiation Laboratory and the Metallurgical Laboratory at the University of Chicago, played important contributing roles. Overall scientific direction of the project was managed by the physicist J. Robert Oppenheimer. In July 1945, the first atomic explosive device, dubbed "Trinity", was detonated in the New Mexico desert. It was fueled by plutonium created at Hanford. In August 1945, two more atomic devices – "Little Boy", a uranium-235 bomb, and "Fat Man", a plutonium bomb – were used against the Japanese cities of Hiroshima
Mark 8 nuclear bomb bomb, was developed as a lightweight airburst (surface target) bomb. The Mark 10 project was cancelled prior to introduction into service, replaced by the much more fissile-material-efficient Mark 12 nuclear bomb implosion design. Mark 8 nuclear bomb The Mark 8 nuclear bomb was a nuclear bomb, designed in the late 1940s and early 1950s, which was in service from 1952 to 1957. The Mark 8 was a gun-type nuclear bomb, which rapidly assembles several critical masses of fissile nuclear material by firing a fissile projectile or "bullet" into a hollow opening in a larger fissile "target", using a system which