The world's first nuclear explosion occurred on July 16, 1945, when a plutonium implosion device was tested at a site located 210 miles south of Los Alamos on the barren plains of the Alamogordo Bombing Range, known as the Jornada del Muerto. Inspired by the poetry of John Donne, J. Robert Oppenheimer code-named the test Trinity. Hoisted atop a 100-foot tower, the plutonium device, or Gadget, detonated at precisely 5:29:45 am Mountain War Time over the New Mexico desert, releasing nearly 21 kilotons of energy, instantly vaporizing the tower and melting the surrounding desert sand and turning it into a green glassy substance, now known as Trinitite. An enormous blast came seconds after the explosion, sending searing heat across the desert and knocking observers to the ground. The success of the Trinity test meant that an atomic bomb using plutonium could be readied for use by the U.S. military.
The Trinity Test: Historic Documents, Photos, and Videos