The Atomic Bomb
Science | Monday, October 19, 2020
Background / History
An Atomic Bomb is a weapon with great destructive and explosive power. They can destroy entire cities,
killing thousands, and causing severe health defects. In the year 1938, a group of nuclear physicists in a
laboratory in Berlin, Germany discovered the Atomic bomb. This was made possible after Otto Hahn,
Lise Meitner, and Fritz Strassman discovered nuclear fission.
On December 28, 1942, President Franklin D. Roosevelt ordered the
formation of The Manhattan Project (which was the code name for
the American-led organization to develop a functional atomic bomb
during WW2)and to bring together various physicists, scientists, and
military officials to combine their nuclear research and to construct
the first Atomic bomb. The main reason for why this project was
started was because of fears that German scientists had already been
working with nuclear weapons since the 1930’s. New Mexico was
where most of the work took place, under the direction of theoretical
physicist J. Robert Oppenheimer, also known as the “father of the
atomic bomb.” On July 16, 1945, in a remote location, the very first
operational atomic bomb was successfully detonated. It created a
huge mushroom cloud around 40,000 feet high.
Hiroshima and Nagasaki Bombings
The U.S. developed 2 types of atomic bombs during World War 2. The first one was called “Little Boy”
and it was a gun-type weapon with a uranium core. And the second one was named “Fat Man” and this
was an implosion-type device with a plutonium core.
As World War 2 ended in April of
1945, the U.S. and Japan soldiers
in the Pacific were still fighting.
President Harry Truman
announced the Potsdam
Declaration. It promised
“prompt and utter destruction”
if Japan did not surrender. On
August 6, 1945, the United
States dropped its first Atomic
bomb from a B-29 bomber plane
over the city of Hiroshima,
Japan. The “Little Boy” exploded
with about 13 kilotons of force
and instantly killed and
estimated 90,000 – 120,000
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people and covering 5 square miles over the city. Since Japan did not surrender immediately, the U.S.
proceeded to drop another atomic bomb named “Fat Man” over the city of Nagasaki, Japan instantly
killing an estimated 60,000 – 70,000 people 3 days later. 7 days later, Japan surrendered to the United
States, and World War 2 came to a stop.
The Science Behind the Atomic Bomb
The destructive power comes from a sudden release of energy
produced by splitting the nuclei of the fissile elements
making up the bombs core. There can be two types of atomic
bombs. The first one being with a uranium core and the
second one being with a plutonium core.
“The isotopes uranium-235 and plutonium-239 were selected
by the atomic
scientists
because they
readily
undergo
fission.
Fission
occurs when a
neutron strikes the nucleus of either isotope, splitting
the nucleus into 2 fragments and releasing a tremendous
amount of energy. The fission process becomes selfsustaining as neutrons produced by the splitting of atom
strike nearby nuclei and produce more fission. This is
known as a
chain reaction and is what causes an atomic explosion.”
(Science Behind the Atom Bomb. (2014, June 05).
Retrieved October 18, 2020, from
https://www.atomicheritage.org/history/sciencebehind-atom-bomb)
Effects
The health effects of nuclear explosions are primarily
due to blast, thermal radiation, initial radiation, and
fallout. Blast – Similar to those created by conventional
explosives, nuclear explosions cause air-blast effects. By
rupturing eardrums or lungs or hurling people at highspeed, the shock wave may directly damage humans,
but most injuries occur because of falling buildings or
airborne debris.
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Thermal Radiation – A single nuclear explosion, unlike traditional blasts, can produce an extreme
thermal radiation pulse that can trigger fires and burn skin over large areas. In certain situations, the fires
that the explosion ignites will turn into a firestorm, preventing survivors from escaping.
Initial Radiation – Significant quantities of neutrons and gamma radiation are emitted by nuclear
detonations.
Fallout – Soil combines with the highly radioactive fission products
from the bomb when a nuclear detonation occurs close to the
ground surface. The debris is borne by the wind and falls over a
period of minutes to hours back down to Earth.
As the damage is done directly after the detonation, the first 3 forms
of effects are known as “prompt” while the radiation dose from
fallout is delivered over a prolonged period.
This is 15-year-old boy who was a victim of the bombing →
There are many long-term effects on human health such as
cataracts, thyroid disease, birth defects, Pneumonia, and Cancer.
They can also get radiation poisoning such as Prodromal syndrome,
Bone Marrow Death, Gastrointestinal Death, and Central Nervous
System Death. When the U.S. bombed Japan, killing thousands of
innocent people, their next generations would be born with birth defects, cancer, and many other
harmful and deadly diseases. As the bombs took out almost 210,000 lives, many of them died in the later
days and weeks due to severe injuries, and severe radiation sickness. Some people in the world today still
have these defects in them and they will continue to because of family DNA.
As of right now, there is strong evidence as to that radiation exposure can cause many severe diseases,
injuries, health effects, cancer, and death. But there is not enough evidence to prove that one day these
defects can resolve, and these humans can return to looking normal without any defects.
Websites Cited
https://www.britannica.com/technology/atomic-bomb/Development-and-proliferation-of-atomic-bombs
https://www.history.com/topics/world-war-ii/atomic-bombhistory#:~:text=A%20discovery%20by%20nuclear%20physicists,sudden%2C%20powerful%20release%20of%20energy.
https://www.atomicheritage.org/history/science-behind-atombomb#:~:text=When%20a%20uranium%2D235%20atom,by%20a%20uranium%2D238%20atom.&text=This%20causes%20a%20nuclear%20chain,this%2
0topic%2C%20see%20Nuclear%20Fission.
https://www.nap.edu/read/11282/chapter/8
https://en.wikipedia.org/wiki/Effects_of_nuclear_explosions_on_human_health
https://www.sciencemag.org/news/2020/07/how-atomic-bomb-survivors-have-transformed-our-understanding-radiation-simpacts#:~:text=%E2%80%9CWe%20want%20to%20work%20with,marrow%20and%20the%20intestinal%20tract.
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