July 16, 1945

The Atomic Age begins. The United States successfully test detonates an atomic bomb at the Trinity Site as part of the Manhattan Project.

At 05:29:45 local time (Mountain War Time), the device exploded with an energy equivalent to around 20 kilotons of TNT (90 TJ). It left a crater of radioactive glass in the desert 10 feet (3 m) deep and 1,100 feet (330 m) wide. At the time of detonation, the surrounding mountains were illuminated "brighter than daytime" for one to two seconds, and the heat was reported as "being as hot as an oven" at the base camp. The observed colors of the illumination ranged from purple to green and eventually to white. The roar of the shock wave took 40 seconds to reach the observers.^[26] The shock wave was felt over 100 miles (160 km) away, and the mushroom cloud reached 7.5 miles (12 km) in height. After the initial euphoria of witnessing the explosion had passed, test director Kenneth Bainbridge commented to Los Alamos director J. Robert Oppenheimer, "Now we are all sons of bitches."^[31] Oppenheimer later stated that, while watching the test, he was reminded of a line from the Hindu scripture the Bhagavad Gita:

Now I am become Death, the destroyer of worlds.^[32][33]

Also, the USS Indianapolis leaves port today. In ten days, the Indianapolis will deliver the parts for the first atomic bomb to Tinian Air Base in the pacific. She will then be sunk by a Japanese submarine on the 30th. The picture below was taken on July 10, 1945.