How They Built the Bomb
Fifty years ago, as war in the Pacific raged, scientists in the American desert knocked on the door of the Atomic Age
A sense of gloom as heavy as the sky overhead pervaded the small group gathered in a crude, concrete-reinforced wooden shelter on the desert of south-central New Mexico in the predawn blackness of Monday, July 16, 1945. Ten thousand yards to the north, in a cab atop a 100-foot steel tower rested a compact device called "the gadget" - the world's first atomic bomb. Everything had been in readiness for the scheduled 4 a.m. firing when the fickle weather had broken its promise. Dripping skies and unfavorable winds now threatened to cancel the long-awaited test.Skip to next paragraph
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Amid the desert underbrush not far from the control shelter, two men stood silently, engulfed in the urgency of the moment. Under ordinary circumstances, they would have had little in common. Prof. J. Robert Oppenheimer, gentle, aesthetic director of the Los Alamos scientific laboratory, was a theoretical physicist and, incidentally, a deep student of literature. Maj. Gen. Leslie Groves, shrewd, hardheaded boss of the Manhattan Project, the highly secret wartime crash program for developing the atom bomb, was an Army engineer, a get-it-done-and-let-the-heads-roll professional soldier with a construction man's inbred skepticism toward egghead scientists.
Yet events of the past three years had drawn these two men into a genuine friendship. As they waited in the early-morning darkness, the heavyset general would sometimes rest his hand with a fatherly gesture on the drooping shoulders of the tall but slightly built scientist. Then they both would look up into the drizzle to see if they could glimpse a few stars or find any other indication of a break in the weather.
Oppenheimer and Groves knew that on the very next day, 6,000 miles away in Potsdam, Germany, the President of the United States was scheduled to sit down with British Prime Minister Winston Churchill and Soviet Premier Joseph Stalin to work out a surrender ultimatum to Japan. And President Truman had been told by Secretary of War Henry Stimson that word was expected by nightfall whether or not an atomic bomb could be the new superweapon that might quickly end the war with Japan.
The weather was only one of dozens of uncertainties that troubled Oppenheimer, Groves, and their colleagues. The scientists felt confident in the correctness of the complex theories they had translated, bit by bit, into the gadget resting atop the tower. But they were dealing with so many untested factors that, in a betting pool, their guesses as to the yield of the device varied from zero to an explosive force equivalent to 18,000 tons of TNT.
Prof. George Kistiakowsky, one of the world's foremost authorities on explosives, considered his guess of 1,400 tons highly optimistic. Many of the laboratory scientists picked figures of only a few hundred tons, which would hardly qualify the atomic bomb as a superweapon or justify the expenditure of the $2 billion it cost.
Since 1939, scientific work toward an atomic bomb had been progressing with utmost secrecy under the leadership of Enrico Fermi, Leo Szilard, Harold Urey, John Wheeler, Eugene Wigner, Arthur Compton, Ernest Lawrence, Niels Bohr, and Oppenheimer.
A vital breakthrough had occured Dec. 2, 1942, at the University of Chicago's "Metallurgical Laboratory" - a security cover name for the atomic-research team working there - when physicists under Fermi produced the world's first controlled nuclear chain reaction.
Soon afterward, Oppenheimer and the vanguard of scientists at the hastily established Los Alamos laboratory had begun assaulting a mountain of theoretical and technical unknowns. And at Oak Ridge, Tenn., and Hanford, Wash., the industry teams of Union Carbide and Carbon, Tennessee Eastman, and duPont had been working all-out to develop engineering processes that would somehow deliver the large amounts of uranium-235 and plutonium required if any bombs were to be made in time to help end the war.
During the 12 months prior to July 1945, a Los Alamos group under Harvard Prof. Kenneth Bainbridge had been working on a desolate New Mexico desert plateau, preparing for the full-scale test of the bomb. Located on a remote section of the Alamogordo Air Base, the site was shielded on the east by the 8,600-foot-high Oscura Mountains and on the south by the San Andres range. The nearest highway was 20 miles away. The closest towns of any size, Socorro and Carrizozo, were 40 miles distant. Alamogordo was 60 miles to the southeast, and Albuquerque was 110 miles to the north.