The Trinity device, the world's first atomic bomb, in place at the top of its support tower in Los Alamos. Standing next to the bomb is Norris Bradbury, the man in charge of the bomb's construction. Trinity was detonated on 16 July, 1945, and had an explosive power equivalent to 21,000 tons of TNT. The device used plutonium as the fission material; several explosive 'lenses' forced small amounts of plutonium together to form the critical mass needed for the explosion. Many wires may be seen leading to the detonators for these lens charges.