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Effects Of The Atomic Bombs On Hiroshima And Nagasaki Essay, Research Paper
Ever since the dawn of time man has found new ways of killing each other. The
most destructive way of killing people known to man would have to be the atomic bomb.
The reason why the atomic bomb is so destructive is that when it is detonated, it has
more than one effect. The effects of the atomic bomb are so great that Nikita
Khrushchev said that the survivors would envy the dead (International Physicians for the
Prevention of Nuclear War, 1982). These devastating physical effects come from the
atomic bomb’s blast, the atomic bomb’s thermal radiation, and the atomic bomb’s
nuclear radiation.
An atomic bomb is any weapon that gets its destructive power from an atom.
This power comes when the matter inside of the atoms is transformed into energy. The
process by which this is done is known as fission. The only two atoms suitable for
fissioning are the uranium isotope U-235 and the plutonium isotope Pu-239 (Outlaw
Labs). Fission occurs when a neutron, a subatomic particle with no electrical charge,
strikes the nucleus of one of these isotopes and causes it to split apart. When the nucleus
is split, a large amount of energy is produced, and more free neutrons are also released.
These neutrons then in turn strike other atoms, which causes more energy to be released.
If this process is repeated, a self-sustaining chain reaction will occur, and it is this chain
reaction that causes the atomic bomb to have its destructive power (World Book, 1990).
This chain reaction can be attained in two different ways.
The first type of atomic bomb ever used was a gun-type. In this type two
subcritical pieces of U-235 are placed in a device similar to the barrel of an artillery
shell. One piece is placed at one end of the barrel and will remain there at rest. The
other subcritical mass is placed at the other end of the barrel. A conventional explosive
is packed behind the second subcritical mass. When the fuse is triggered, a conventional
explosion causes the second subcritical mass to be propelled at a high velocity into the
first subcritical mass. The resulting combination causes the two subcritical masses to
become a supercritical mass. When this supercritical mass is obtained, a rapid
self-sustained chain reaction is caused (World Book, 1990). This type of atomic bomb
was used on Hiroshima, and given the nickname “Little Boy” after Franklin D. Roosevelt
(Outlaw Labs).
The second type of atomic bomb is an implosion bomb. In this type a subcritical
mass, which is in the shape of a ball, is placed in the center of the weapon. This
subcritical mass is surrounded in a spherical arrangement of conventional explosives.
When the fuse is triggered all of the conventional explosives explode at the same time.
This causes the subcritical mass to be compressed into a smaller volume, thus creating a
supercritical mass to be formed. After this supercritical mass is obtained, a self-sustained
chain reaction takes place and causes the atomic explosion (World Book, 1990). This
type of stomic bomb was used on Nagasaki, and given the nickname “Fat Man” after
Winston Churchill (Outlaw Labs).
The blast from an atomic bomb’s explosion will last for only one-half to one
second, but in this amount of time a great deal of damage is done (Physicians and
Scientists on Nuclear War, 1981). A fireball is created by the blast, which consists
mainly of dust and gasses. The dust produced in this fireball has no substantial effect on
humans or their environment. However, as the gasses expand a blast wave is produced.
As this blast wave moves, it creates static overpressure. This static overpressure then in
turn creates dynamic pressure. The static overpressure has the power to crush buildings.
The dynamic pressure creates winds, which have the power to blow down trees
(International Physicians for the Prevention of Nuclear War, 1982). The blast pressure
and fireball together only last for approximately eleven seconds, but because it contaitns
fifty percent of the atomic bomb’s latent energy a great deal of destruction occures (The
Committee for the Compilation of Materials on Damage Caused by the Atomic Bombs in
Hiroshima and Nagasaki, 1981).
In Hiroshima the blast from the atomic bomb was measured to be about four and
a half to six and seven tenths tons of pressure per square mere, while in Nagasaki the
blast was measured to be about six to eight tons of pressure per square meter
(International Physicians for the Prevention of Nuclear War, 1982). Because of thsi
dramatic change in the pressure most of the cities were destroyed. The static
overpressure in Hiroshima caused ninety-one and nine tenths percent of all the buildings
to be destroyed, while in Nagasaki it casued thirty-six and one tenth of all of the
buildings to be destroyed. The static overpressure created a dynamic pressure that had
winds up to four hundred miles per hour (The Committee for the Compilation of
Materials on Damage Caused by the Atomic Bombs in Hiroshima and Nagasaki, 1981).
These winds caused minor scrathces, lacerations, or compound fractures, which came
about when people and glass fragments were projected through the air. By combining the
results of the static overpressure and the dynamic pressure on can begin to see what
damage was caused by the atomic bomb’s blast. The total number affected in Hiroshima
was approximately seventy-eight thousand people, while in Nagasaki the total number
affected was approximately forty-five thousand people (International Physicians for the
Prevention of Nuclear War, 1982).
The thermal radiation produced by an atomic bomb explosion will account for
thirty-five percent of the atomic bomb’s damage. Thermal radiation can come in either
one of three forms; ultraviolet radiation, visible radiation, or infrared radiation. The
ultraviolet radiation is absorbed so rapidly by air particles that it has no substantial effect
on people (World Book, 1990). However, the visible and infrared radiation creates an
enormous amount of heat to be produced, approximately ten million degrees Celsius at
the hypocenter (Physicians and Scientists on Nuclear War, 1981). This heat has two
main effects. The first is known as flash burns. These flash burns are produced by the
flash of thermal radiation right after the explosion. Flash burns can be either first degree
burns (bad sun burns), second degree burns ( blisters, infections, and scars), or third
degree burns (destroyed skin tissue). The second type is known as flame burns. These
are burns that come from one of two different types of fires, which are created when
flammable materials are ignited by the thermal radiation. The first type is called
firestorms. A firestorm is violent, has raging winds, and has extremely high
temperatures; but fortunately it does not spread very rapidly. The second type is called a
conflagration. A conflagration is when the fire spreads in a front (International
Physicians for the Prevention of Nuclear War, 1982). The thermal radiation produced by
the atomic bomb’s explosion will account for most of the deaths or injuries.
In Hiroshima and Nagasaki the thermal radiation accounted for approximately
twenty to thirty percent of the deaths or injuries from the atomic bomb’s explosion.
Those that were at a distance of four and two hundredths of a kilometer from the
hypocenter received first degree burns. Those that were at a distance of three and one
half kilometers from the hypocenter received second degree burns. Those that were at a
distance of ninety-seven hundredths of a kilometer from the hypocenter received third
degree burns (International Physicains for the Prevention of Nuclear War, 1982).
Ninety-five percent of the burns created from the thermal radiation were by flash burns,
and only five percent of the burns were by flame burns. The reason for this low number
of flame burns is that only two to ten percent of the buildings caught on fire
(International Physicians for the Prevention of Nuclear War, 1982). By combining the
damage from both the flash and flame burns one can begin to see the effects that an
atomic bomb’s thermal radiation had. Approximately sixty thousand in Hiroshima, and
approximately forty-one thousand people were either killed or injured from the thermal
radiation (The Committee for the Compliation of Materials on Damage Caused by the
Atomic Bombs in Hiroshima and Nagasaki, 1981).
The final effect that an atomic bomb caused is the nuclear radiation produced
from the fission process. The cuclear radiation comes in the form of either Gamma rays
or Beta particles. Gamma rays are electromagnetic radiation originating in the atomic
nuclei, physically identical to x-rays. They can enter into living tissue extremely easily.
Beta particles are negatively charged particles, identical to an electron moving at a high
velocity (International Physicians for the Prevention of Nuclear War, 1982). These forms
of nuclear radiation are measured in rads (radiation-absorbed-dose), which is defined as
teh absorption of five ten millionths joule per gram of abosorbing material (International
Physicians for the Prevention of Nuclear War, 1982). During the initial nuclear radiation
mostly Gamma rays are emitted from the fireball. This period of initial nuclear radiation
lasts for approximately one minute. During the residual nuclear period (fallout) the Beta
particles and more of the Gamma rays are emitted. The residual radiation has two stages:
early fallout and delayed fallout. In early fallout, the heavyand highly radioactive
particles fall back to the earth, usually within the first twenty-four hours. In delayed
fallout, the tiny and often invisible particles fall back to the earth, and usually last from a
couple od days to several years (Physicians and Scientists on Nuclear War, 1981 and
World Book, 1990). The nuclear radiation from the atomic bomb’s explosion was not
the main cause of death, but it did still have serious results.
In Hiroshima, the initial nuclear radiation was spread over a distance of
approximately fifty-three hundredths of a kilometer. In Nagasaki, the initial nuclear
radiation only spread one and six thousandths of a kilometer (The Committee for the
Compilation of Materials on Damage Caused by the Atomic Bombs in Hiroshima nad
Nagasaki, 1981). The reason why the nuclear radiation was not the main caused of
deaths or injuries was that the atomic bomb was detonated so high in the atmosphere;
approximately five hundred and seventy meters in Hiroshima, and approximately five
hundred and ten meters in Nagasaki (Outlaw Labs). Even without causing many deaths
the nuclear radiation probably caused the most serious effects. Those with definite proof
were those of increased rates of cataracts, leukemia, cancer of the thyroid, cancer of the
breast, cancer of the lungs, cancer of the stomach, and mental retardation on babies in
utero. Those that had substantial but not definite proof were those of tumors of the
esophagus, tumors of the colon, tumors of the salivary glands, and tumors of the urinary
tract organs. Those that had no definite nor substantial proof were those of increased
rates of birth mortality, birth defects, infertility, and susceptibility towards illnesses
(Physicians and Scientists on Nuclear War, 1981). The total number of people effected
by the nuclear radiation was estimated to be thiry-five thousand people in Hiroshima, and
twenty-one thousand people in Nagasaki (The Committee on Damage Caused by the
Atomic Bomb in Hiroshima and Nagasaki).
Either the blast, the thermal radiation, or the nuclear radiation from an atomic
bomb explosion will have severe effects on both humans and on the environment in
which they live in. The only two cities that have ever experienced having an atomic
bomb being exploded on them were the Japanese cities of Hiroshima and Nagasaki
during World War II. In Hirsohima, the total number killed was one hundred and
eithteen thousand six hundred and sixty-one. The total number severely injured was
thrity thousand five hundred and twenty-four. The number slightly injured was
forty-eight thousadn six hundred and six. The total number missing was three thousand
and six hundred and seventy-seven. In Nagasaki, the total number killed was
seventy-three thousand eitght hundred and eighty-four. The total number severely
injured was seventy-four thousand nine hundred and nine. The total number slightly
injured was one hundred and twenty thousand eight hundred and twenty (The Committee
for the Compliation of Materials on Damage Caused by the Atomic Bombs in Hiroshima
and Nagasaki, 1981). With statistics like these it is clearly seen that Pope John Paul II
was right when he said,
“Any nuclear war would inevitably cause death, disease, and suffering of
pandemic proportions and without the possibility of effective medical
intervention. The only hope for humanity is prevention of any form of Nuclear
War.
The examples of Hiroshima and Nagasaki will hopefully be the first and the last time that
the power of the atomic bomb will ever be used.