Less than two weeks after the testing of Trinity, the Enola Gay released Little Boy – a gun-type fission weapon fuelled by the nuclear fission of uranium-235 – over central Hiroshima shortly after 8am local time. The radioactive plume from the bomb dropped on Nagasaki City seen from 10km away in Koyagi-jima, Japan GettyĪn order was given to drop the atomic bomb on Japan on 25 July. He translated it as: "I become death, the destroyer of worlds." Trinity was an implosion-design plutonium device, the same design of weapon that would later be used to devastate Nagasaki.Īfter witnessing the blast, Julius Robert Oppenheimer, one of the key physicians in the Manhattan Project, later said he recalled a verse from the Hindu text, the Bhagavad Gita.
Marking the beginning of the nuclear age, the flash light from the blast – which measured 20 kilotons of TNT – was seen across New Mexico as well as parts of Arizona, Texas and Mexico. The US government tested its first nuclear weapon, code-named Trinity, in the Jornada del Muerto desert in New Mexico on 16 July 1945. The Manhattan Project was launched in 1942 with the co-operation of Britain and Canada and grew to employ more than 130,000 scientists, engineers and workers. It stated a bomb of unprecedented power could be created from the forces of nuclear fission, warning Nazi Germany may be working on creating such a weapon.įearing the devastation such a device could yield in Nazi hands, Einstein and Szilard urged the US government to join the race to create the first atomic bomb. In October 1939, shortly after the outbreak of the Second World War, US president Franklin Roosevelt received a letter from Albert Einstein and his Hungarian colleague Leo Szilard.
From the first hydrogen device to the Soviet Union's detonation of a weapon with 1,400 times the combined power of Hiroshima and Nagasaki, more than 2,000 nuclear tests have been carried out since 1945. Yet despite the devastation the two bombs unleashed, they are far from the most powerful nuclear weapons ever built. 70th anniversary of the atomic bombs that ended the Second World WarĪ second, larger atomic bomb was released over Nagasaki three days later, bringing the final death toll of both attacks, the only times nuclear weapons have been used in war, to an estimated 200,000.