At 05:29 AM on 16 July 1945, the United States detonated the world's first nuclear device — code-named "The Gadget" — at the Trinity test site in the Jornada del Muerto desert, New Mexico. The explosion released energy equivalent to approximately 21 kilotons of TNT, vaporising the 100-foot steel tower and turning the desert sand into a green glass called trinitite.
Test director J. Robert Oppenheimer later recalled the Hindu scripture the *Bhagavad Gita*: *"Now I am become Death, the destroyer of worlds."* Secretary of War Henry Stimson called it *"the most terrible weapon ever known in human history."*
Three weeks later, atomic bombs were dropped on Hiroshima (6 August) and Nagasaki (9 August), killing between 129,000 and 226,000 people and prompting Japan's surrender. Trinity opened the nuclear age and initiated an arms race between the United States and Soviet Union that defined the Cold War for the next four decades — and whose consequences remain with us today.