North Field, Tinian Island, Mariana Archipelago.
Photographer: Manhattan Project Engineers.
Moments away from being lifted into the bomb bay of the B-29 Superfortress Enola Gay, and a few hours short of stunning earth with the explosive power of a splitting atom; the world’s first atom bomb waits to change the very concept of warfare with a towering mushroom cloud, in this photo taken on the 5th of August, 1945.
Codenamed ‘Little Boy’, after U.S. president Harry S. Truman, the cigar-shaped bomb was 10 feet long and 28 inches in diameter. It was the first of the only two atom bombs to be used till date, and in 1945 the only one to be produced out of uranium 235. An isotope so rare and hard to separate from the more abundant isotope of 238, that if a second of its type was needed, it would have taken several more months to put together.
Created at the Los Alamos Laboratory, now the Los Alamos National Laboratory. A U.S. institution into advancing science and technology for defence purposes. The atom bomb was the brainchild of American geophysicist Francis Birch. Developed after its predecessor, the plutonium-based ‘Thin Man’ had been scrapped for developing a fatal incompatibility.
Designed as a gun-type fission device, it had been pre-configured to fire through a uranium barrel, a hollow uranium bullet of subcritical mass into a uranium target of also subcritical mass to produce the chain reaction required for the atomic explosion. The bomb was almost wholly made out of isotope 235. Weighing some 9,700 pounds and containing within its uranium casing, an explosive strength equivalent to 15,000 TNT.
How Uranium was procured for the atomic bomb.
As uranium ore at the time had been a rare resource and not in stockpile in the U.S. The ‘Little Boy’ had been produced in stages as and when the metal had become available for refinement and use. The first batch of 1,200 pounds that had gone into its making had come from the Shinkolobwe Mines located in the Katanga province of the Republic of Congo, Africa. Then a Belgian colony with the mine owned by the Belgian company of Union Minière du Haut-Katanga.
The second portion, another 1,200 pounds, had been procured from a German installation in Germany. While the third, a batch of 1,000 odd pounds of uranium oxide, had come from a captured German submarine, headed for Japan with the rare metal and advanced weaponry technology, in May 1945.
Completed in June 1945, after having its components manufactured in different installation plants across the U.S., in what had been a highly classified and clandestine operation. The ‘Little Boy’ had been ferried in parts to the island of Tinian in the Mariana Archipelago to be assembled inside mechanic shacks at North Field Air Base.
The entire assemblage had taken place under the constant monitoring and supervision of trained technicians associated with the Manhattan Project. A colossal undertaking of military divisions, universities and eminent scientists, tasked with researching and developing atomic weapons in top secrecy. Originally a small experiment funded by U.S. President Roosevelt at the onset of World War II in 1939, the project had burgeoned overnight, after the unprovoked Japanese attack on Pearl Harbour, on the 7th of December 1941.
Release over Hiroshima.
Released over Hiroshima, on the 6th of August 1945, the ‘Little Boy’ had detonated after a pre-configured delay of 43 seconds. A fraction of time during which, pulled by the earth’s gravity, it had plummeted through 6 miles of air, and then exploded over its designated target – the T-shaped Aioia Bridge spanning the Ota River.
On detonation, the bomb had generated a heat of around 2,99,726 degrees Celsius in the air, and 5,726 degrees Celsius on the ground. The blast and the firestorm it had created had resulted in the instantaneous incineration of those nearest to its epicentre. Resulting in the death of a speculated 30% of the city’s population.
In terms of infrastructural damage, an estimated 4.7 square miles of Hiroshima had been razed into the ground with 48,000 buildings completely demolished. In later months radiation poisoning and cancer had claimed more lives, taking the number of deaths to a speculated 2,37,000 people.
A Flawed Weapon.
Yet and in spite of the wide-scale death and destruction, the bomb, however, had failed to accomplish its intended purpose. Which was the immediate surrender of Japan. Moreover, it had also turned out to be flawed. Out of the 140 pounds of uranium fuel it contained. Only 1.38% had actually fissioned, proving it was not as destructive as it had been created to be.
The volatile weapon had also posed a great danger to the crew of the B-29 Super Fortress, Enola Gay. The bomber that had delivered the bomb to its target in Japan (see Farbound.Net story: Harbinger of the nuclear age),escorted by six other bombers of its type. Furthermore, owing to the covert nature of the mission, the handpicked crewmen had been kept in the dark – till their last-minute debriefing on the 5th of August, 1945.
The only person acquainted with its destructive power was Lieutenant Colonel Paul Tibbets, commander of the 509th Corps and pilot of the Enola Gay. A 29-year-old decorated veteran and a bomber captain with a record of having released over 200 bombs over enemy-held territory in Europe and Africa. Tibbets, nonetheless, had remained sceptical of its potential, till he had witnessed the destruction below with his own eyes.
Catalogued by the U.S. National Archives and Records Administration (NARA), this photo was possibly captured by an engineer or technician of the Manhattan Project. Entasked with the responsibility of documenting each and every step. The National Archives credits this photo to Record Group 77. The War Department, Office of the Chief of Engineers. Manhattan Engineer District. The photo is dated: August 1945.
