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 10 nuclear bomb Mark 10 nuclear bomb The Mark 10 nuclear bomb was a proposed American nuclear bomb based on the earlier Mark 8 nuclear bomb design. The Mark 10, like the Mark 8, is a Gun-type nuclear weapon, 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 closely resembles a medium-sized cannon barrel and propellant. The Mark 10 was intended to be a general purpose airburst nuclear weapon, unlike the Mark 8 which was intended to penetrate into the ground as