world war ii: manhattan project

Calutron operators at their panels, in the Y-12 plant at Oak Ridge, TN during World War II, circa 1943. The calutrons were used to refine uranium ore into fissile material. During the Manhattan Project effort to construct an atomic weapon, employees toiled in secrecy, most having no idea what they were actually working on. Gladys Owens, the woman seated in the foreground, didn’t understand the exact purpose of her job until seeing this photo in a public tour of the facility fifty years later.

“Following the July 26 Potsdam Declaration, where Allies outlined the terms of surrender for Japan and promised "inevitable and complete destruction” of Japan if they failed to comply, preparations were secretly under way to make use of the newly-tested Atomic Bomb. Here, the first nuclear device to be used as a weapon, codenamed ‘Little Boy’, rests on trailer cradle in a pit, ready for loading into the bomb bay of the 'Enola Gay’ in August of 1945.“

(National Archives)

“In July of 1945, the United States was in the final stages of developing a powerful and deadly new weapon - the Atomic Bomb. Here, Los Alamos director J. Robert Oppenheimer is seen in silhouette as he oversees final assembly of "The Gadget”, the first nuclear device to be detonated, at the Trinity test site in New Mexico.“

(US DoD)