July 16, 1945: The U.S. conducts the first successful atomic bomb test.
J. Robert Oppenheimer later remarked that, as he witnessed the detonation of “the Gadget" in the Jornada del Muerto desert of New Mexico during the Trinity nuclear test, he was reminded of a quote from the Bhagavad Gita:“Now I am become Death, the destroyer of worlds."
Oppenheimer, a professor and physicist, was a key figure of the Manhattan Project, which ran from 1941 to 1946 and sought to place in American hands the power of fission before Nazi Germany could develop the technology in a usable form. The Project combined American and British resources, industrial power, money, and information, with the top scientific minds from both nations and exiled scientists from Germany and Austria. The Trinity test was the first successful detonation of a nuclear device, and it was a product of Project Manhattan. Conducted by the U.S. Army under Lieutenant General Leslie Groves, it was designed to resemble a drop from an airplane (as to accurately measure the effects of such an attack), in this test simulated by a 100-foot-tall steel tower, from which the plutonium-core device was raised. The detonation occurred at approximately 5:29 AM; onlookers - mostly scientists and military officials - observed from stations ten to twenty miles away from ground zero.
The successful Trinity test marked the beginning of a new age: an Atomic Age. This less refined version of the era’s new superweapon exploded with an energy of approximately 20 kilotons. It created a mushroom cloud 12 kilometers high; it left behind a crater 1,000 feet wide; it generated heat described as 10,000 times hotter than the surface of the sun; and it was only the beginning. One member of Leslie Groves’ staff described the effects of the detonation as "unprecedented, magnificent, beautiful, stupendous and terrifying," writing that “no man-made phenomenon of such tremendous power had ever occurred before."