THE ATOMIC BOMBING OF HIROSHIMA
Hiroshima (August 6, 1945)
Events: Dawn of the Atomic Era, 1945
In the early morning hours of August 6, 1945, a B-29 bomber
named Enola Gay took off from the island of Tinian and headed north
by northwest toward Japan. The bomber's primary target was the city
of Hiroshima, located on the deltas of southwestern Honshu Island facing
the Inland Sea. Hiroshima had a civilian population of almost 300,000 and
was an important military center, containing about 43,000 soldiers.
The bomber, piloted by the commander of the 509th Composite Group,
Colonel Paul Tibbets, flew at low altitude on automatic pilot before climbing to
31,000 feet as it neared the target area. At approximately 8:15 a.m.
Hiroshima time the Enola Gay released "Little Boy," its 9,700-pound uranium
bomb, over the city. Tibbets immediately dove away to avoid the anticipated
shock wave. Forty-three seconds later, a huge explosion lit the morning sky
as Little Boy detonated 1,900 feet above the city, directly over a parade field
where soldiers of the Japanese Second Army were doing calisthenics. Though already
eleven and a half miles away, the Enola Gay was rocked by the blast. At
first, Tibbets thought he was taking flak. After a second shock wave
(reflected from the ground) hit the
plane, the crew looked back at Hiroshima. "The city was hidden by
that awful cloud . . . boiling up, mushrooming, terrible and incredibly
tall," Tibbets recalled. The yield of the explosion was later
estimated at 15 kilotons (the equivalent of 15,000 tons of TNT).
On the ground moments before the blast it was a calm and sunny
Monday morning. An air raid alert from earlier that morning had been
called off after only a solitary aircraft was seen (the weather plane), and by
8:15 the city was alive with activity -- soldiers doing their morning
calisthenics, commuters on foot or on bicycles, groups of women and
children working outside to clear firebreaks. 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. One boy was blown through the windows of his house and across the
street as the house collapsed behind him. Within minutes 9 out of 10
people half a mile or less from ground zero were dead.
People farther from the point of detonation experienced first
the flash and heat, followed seconds later by a deafening boom and the blast wave.
Nearly every structure within one mile of ground zero was destroyed, and almost
every building within three miles was damaged. Less than 10 percent of the
buildings in the city survived without any damage, and the blast wave shattered glass in suburbs twelve miles away. The most common first reaction of
those that were indoors even miles from ground zero was that their building had just
suffered a direct hit by a bomb. Small ad hoc rescue parties soon began to
operate, but roughly half of the city's population was dead or injured. In
those areas most seriously affected virtually no one escaped serious
injury. The numerous small fires that erupted simultaneously all around
the city soon merged into one large firestorm,
creating extremely strong winds that blew towards the center of the fire.
The firestorm eventually engulfed 4.4 square miles of the city, killing anyone
who had not escaped in the first minutes after the attack. One postwar
study of the victims of Hiroshima found that less than 4.5 percent of survivors
suffered leg fractures. Such injuries were not uncommon; it was just that
most who could not walk were engulfed by the firestorm.
Even after the flames had subsided, relief from the outside was slow in
coming. For hours after the attack the Japanese government did not even
know for sure what had happened. Radio and telegraph communications with
Hiroshima had suddenly ended at 8:16 a.m., and vague reports of some sort of
large explosion had begun to filter in, but the Japanese high command knew that
no large-scale air raid had taken place over the city and that there were no
large stores of explosives there. Eventually a Japanese staff officer was
dispatched by plane to survey the city from overhead, and while he was still
nearly 100 miles away from the city he began to report on a huge cloud of smoke
that hung over it. The first confirmation of exactly what had happened
came only sixteen hours later with the announcement of the bombing by the United
States. Relief workers from outside the city eventually began to
arrive and the situation stabilized somewhat. Power in undamaged areas of
the city was even restored on August 7th, with limited rail service resuming the
following day. 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.
No one will ever know for certain how many died as a
result of the attack on Hiroshima. Some 70,000 people probably died as a
result of initial blast, heat, and radiation effects. This included about
twenty American airmen being held as prisoners in the city. By the end of 1945,
because of the lingering effects of radioactive fallout
and other after effects, the
Hiroshima death toll was probably over 100,000. The five-year death
total may have reached or even exceeded 200,000, as cancer and other long-term
effects took hold.
At 11:00 a.m., August 6 (Washington D.C. time), radio stations began playing a
prepared statement from President Truman
(right) informing the American public that the United States had dropped an entirely new
type of bomb on the Japanese city of Hiroshima -- an "atomic bomb."
Truman warned that if Japan still refused
to surrender unconditionally, as demanded by the Potsdam Declaration of July 26,
the United States would attack additional targets with equally devastating
results. Two days later, on August 8, the Soviet Union declared war on
Japan and attacked Japanese forces in Manchuria, ending American hopes that the
war would end before Russian entry into the Pacific theater. By August 9th, American aircraft were showering
leaflets all over Japan informing its people that "We are in possession of
the most destructive explosive ever devised by man. A single one of our
newly developed atomic bombs is actually the equivalent in explosive power to
what 2,000 of our giant B-29s can carry on a single mission. This awful
fact is one for you to ponder and we solemnly assure you it is grimly
accurate. We have just begun to to use this weapon against your
homeland. If you still have any doubt, make inquiry as to what happened to
Hiroshima when just one atomic bomb fell on that city." Meanwhile,
Tibbets's bomber group was simply waiting for the weather to clear in order to drop
its
next bomb, the plutonium weapon nicknamed "Fat
Man" (right) that was destined for the city of Nagasaki.
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