August 6 and 9, 1945 - Atomic Bombings of Hiroshima and Nagasaki
Up to August 6th, occasional bombs, which did no great damage had fallen on Hiroshima. Many cities roundabout, one after the other were destroyed, but Hiroshima itself remained protected. There was almost daily observation planes over the city but none of them dropped a bomb. The citizens wondered why they alone had remained undisturbed for so long a time. There were fantastic rumors that the enemy had something special in mind for this city, but no one dreamed that the end would come in such a fashion as on the morning of August 6th.
August 6th began in a bright, clear, summer morning. About 7 o'clock, there
was an air raid alarm which we had heard almost every day and a few planes
appeared over the city. No one paid attention and at about 8:00, the all-clear
sounded. The time is approximately 8:15 -- the whole valley is filled by a
garish light which resembles the Magnesium light used in photography. Minutes
later huge mushroom cloud formed over the city and city was burning like 'hell'
with temperature soaring to millions of centigrade. The cloud is estimated to
have reached a height of 40,000 feet.
On August 6, 1945, a US B-29 plane, dropped a uranium atomic bomb, code named "Little Boy" on Hiroshima, Japan's seventh largest city. In minutes, half of the city vanished. According to U.S. estimates, 60,000 to 70,000 people were killed or missing, 140,000 were injured many more were made homeless as a result of the bomb. Deadly radiation reached over 100,000. In the blast, thousands died instantly. The city was unbelievably devastated. Of its 90,000 buildings, over 60,000 were demolished...
Those closest to the explosion died instantly, their bodies turned to black char. Nearby birds burst into flames in mid-air, and dry, combustible materials such as paper instantly ignited as far away as 6,400 feet from ground zero. The white light acted as a giant flashbulb, burning the dark patterns of clothing onto skin (right) and the shadows of bodies onto walls. Survivors outdoors close to the blast generally describe a literally blinding light combined with a sudden and overwhelming wave of heat. (The effects of radiation are usually not immediately apparent.) The blast wave followed almost instantly for those close-in, often knocking them from their feet. Those that were indoors were usually spared the flash burns, but flying glass from broken windows filled most rooms, and all but the very strongest structures collapsed. Within minutes 9 out of 10 people half a mile or less from ground zero were dead.
Several days after the blast, however, medical staff began to recognize the first symptoms of radiation sickness among the survivors. Soon the death rate actually began to climb again as patients who had appeared to be recovering began suffering from this strange new illness. Deaths from radiation sickness did not peak until three to four weeks after the attacks and did not taper off until seven to eight weeks after the attack. Long-range health dangers associated with radiation exposure, such as an increased danger of cancer, would linger for the rest of the victims' lives, as would the psychological effects of the attack.
Little Boy" was created using uranium-235, a radioactive isotope of uranium.
This uranium-235 atomic bomb, a product of $2 billion of research, had never
been tested. Nor had any atomic bomb yet been dropped from a plane. Some
scientists and politicians pushed for not warning Japan of the bombing in order
to save face in case the bomb malfunctioned.
On August 9th, three days later, at 11:02 A.M., another B-29 dropped the second
- a plutonium bomb, nicknamed "Fat Man, on the industrial section of the city of Nagasaki, totally destroying 1 1/2 square miles of the city, killing 39,000 persons, and injuring 25,000 more.At an altitude of 1,650 feet, Fat Man exploded over Nagasaki. The yield of the explosion was later estimated at 21 kilotons, 40 percent greater than that of the Hiroshima bomb.
Nagasaki was an industrial center and major port but no more. Although the destruction at Nagasaki has generally received less worldwide attention than that at Hiroshima, it was extensive nonetheless. Almost everything up to half a mile from ground zero was completely destroyed, including even the earthquake-hardened concrete structures that had sometimes survived at comparable distances at Hiroshima. Men and animals died almost instantly within 1 kilometer (0.62 miles) of the point of detonation. Almost all homes within a mile and a half were destroyed, and dry, combustible materials such as paper instantly burst into flames as far away as 10,000 feet from ground zero. Of the 52,000 homes in Nagasaki, 14,000 were destroyed and 5,400 more seriously damaged. Only 12 percent of the homes escaped unscathed.
There had been four cities chosen as possible targets: Hiroshima, Kokura, Nagasaki, and Niigata. The cities were chosen because they had been relatively untouched during the war. The Target Committee wanted the first bomb to be "sufficiently spectacular for the importance of the weapon to be internationally recognized when publicity on it was released."
The United States, with assistance from the United Kingdom and Canada, designed and built the first atomic bombs under what was called the Manhattan Project.
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