FIRST ATOMIC BOMB DEVELOPMENT
& CONTAMINATION INCIDENTS
By: Heidy Sosa
- The World’s First Atomic Bomb (Introduction) 3
- How it all began! 4
- The Manhattan Project 5
- Trinity 7
- Attack on Pearl Harbor 10
- Attack on Hiroshima 11
- Radiation Exposure 13
- Aftermath 16
- Reference 17
THE WORLD’S FIRST ATOMIC BOMB
It all started during World War II, the Americans were trying to win the race against
Nazi Germany to create the first atomic bomb.
The establishment for development of the atomic bomb was named, the Manhattan
Project. It led to the invention of two of the most destructive atomic bombs.
The Japanese denied to surrender. Therefore, two atomic bombs were dropped on
Japanese cities. One of them being Hiroshima and the other one was the city of
Nagasaki. Causing great devastation.
These attacks forced Japan to surrender and ended WWII , however, these attacks
killed and injured over 200,000 people and also raised the questions about the
implications of nuclear weapons.
HOW IT ALL BEGAN!
In 1938, German scientists discovered fission, which occurs when the nucleus of an
atom breaks into two equal parts. Neutrons are released to break up atoms, causing
a chain reaction. It was thought that fission could cause an explosion of great force.
The Germans planned on building the first nuclear weapon to have advantage over
all the other countries.
As soon as Albert Einstein found out about Germanys desire to develop the first
atomic bomb, he alerted the U.S. president in 1939; which at the time was Franklin D.
Einstein was hesitant at first. He thought that the government would reject the thought
of creating a weapon that could potentially kill millions of people. However, he
couldn’t allow Nazi Germany to have that advantage.
Einstein explained the potential uses of the atomic bomb and ways that it would help
scientists in their research. Due to his persuasion, president Roosevelt decided to
create the Advisory Committee on Uranium in October of 1939.
THE MANHATTAN PROJECT
This project originated in Manhattan, New York, where scientists studied the different
components of an atomic bomb. It was first founded in 1939 by President Franklin D.
The Manhattan Project was started in response to fears that German scientists had been
working on a weapon using nuclear technology.
The project brought together scientists from the United States, Great Britain, and Canada to
study the feasibility of building an atomic bomb capable of unimaginable destructive power.
The U.S. military teamed up with the best minds of the scientific community to covert the
concept of the atomic bomb to reality.
At first, Roosevelt set up the Advisory Committee on Uranium, a team of scientists and military
officials tasked with researching uranium’s potential role as a weapon. They focused on
radioactive isotope separation and nuclear chain reactions.
Overall, the U.S. spent two billion dollars on this project.
On December 28, 1942, Roosevelt authorized the formation of the Manhattan Project
to combine these various research efforts with the goal of weaponizing nuclear
energy. Facilities were set up in isolated locations such as New Mexico, Tennessee,
and Washington, as well as Canada.
J. Robert Oppenheimer was a physicist named director of the Los Alamos Laboratory
in 1943. The Los Alamos Laboratory was were the first Manhattan Project bombs
were built and tested.
On April 12, 1945, President Roosevelt died and Vice President Harry S. Truman
On July 16, 1945, scientist, army personnel, and technicians anxiously waited for the
first test bomb to drop.
This test bomb took place in the desert of New Mexico, a location known as Jordana
del Muerto. It was code-named “Trinity”.
No one knew what to expect. Some scientists feared it would be the end of the world.
The target in this test was a tower, as soon as the flashes, wave of heat, shock wave,
and mushroom cloud 40,000 feet high, vanished, the tower was completely
disintegrated and thousands of yards of surrounding land turned into a radioactive
glass of a bright jade green color.
The bomb was a success.
The bright light from the Trinity test stood out for hundreds of miles.
The men who created the bomb witnessed the explosion, and were astonished.
Physicist Isidor Rabi expressed that he worried mankind had become a treat and
upset the equilibrium of nature. The instability amongst the witnesses led to petitions.
Some argued that the terrible thing they had created couldn’t be let loose in the
world. Obviously, the petition got ignored.
Two months after the Trinity test, the Germans surrendered. However, Japan refused
to surrender. The last thing the U.S. wanted was a ground war with Japan, so they
decided to drop the first atomic bomb.
Little was known about the dangers of radiation exposure in the 1940s, so local
residents were not warned or evacuated before the test.
People in surrounding areas were exposed to radiation by breathing contaminated
air, eating contaminated foods, and drinking affected water and milk. Some ranches
were located within 15 miles of ground zero, and commercial crops were grown
ATTACK ON PEARL HARBOR
Pear Harbor , Hawaii, the headquarters of the U.S. Pacific fleet was attacked by the
Japanese on December 7, 1941.
The U.S. declared war on Japan the next day and started World War II.
At this moment, president Roosevelt decided it was the time to support the creation of
the atomic bomb.
Researchers built extraction systems, used their knowledge and skills to devise a
process to magnetically separate uranium and plutonium isotopes, and on December
2, 1942 scientists were able to create the first successful chain reaction that allowed
atoms to split in a controlled environment.
Scientists worked diligently, but it took until 1945 to produce the first nuclear
ATTACK ON HIROSHIMA
On August 6, 1945, a uranium bomb named “Little Boy” was dropped.
At 8:15 in the morning the bomb was dropped and at 8:16 over 66,000 people near
ground zero were already dead.
Around 69,000 people were injured, mostly burned or suffering from radiation
The atomic bomb produced complete devastation. It left a “total vaporization” zone of
one-half mile in diameter. The “total destruction” area to one mile, while the impact of
a “severe blast” was felt for two miles. Anything that was flammable within two and a
half miles was burned, and blazing infernos were seen up to three miles away.
The force of the explosion was more than 15,000 tons of TNT, instantly devastating five
square miles of the city. More than 67 percent of the city’s structures were destroyed or
On August 9, 1945, Japan still refused to surrender , therefore, a second bomb
named “Fat Boy” was dropped over Nagasaki.
The two bombs combined killed more than 100,000 people and leveled the two
Japanese cities to the ground.
Japan surrendered on August 14, 1945, bringing an end to WWII.
During the Trinity test bomb little was known about the dangers of radiation exposure
in the 1940s, as a result, people in surrounding areas were exposed to radiation by
breathing contaminated air, eating contaminated foods, and drinking affected water
and milk. Around nearby ranches, exposure rates around 15 Roentgen per hour were
measured just three hours after detonation.
According to the Japanese people, the early symptons suffered from radiation injury
resembled the symptons observed in patients receiving intensive roentgen therapy.
The important symptoms reported by the Japanese and observed by American
authorities were epilation (lose of hair), petechiae (bleeding into the skin), and other
hemorrhagic manifestations, oropharyngeal lesions (inflammation of the mouth and
throat), vomiting, diarrhea, and fever.
Within the first few months after the bombing between 90,000 and 166,000 people
died in Hiroshima, while another 60,000 to 80,000 died in Nagasaki.
The most deadly long-term effects suffered by atomic bomb survivors was leukemia.
An increase in leukemia appeared about two years after the attacks and peaked
around four to six years later.
The Radiation Effects Research Foundation estimates the attributable risk of leukemia
to be 46% for bomb victims.
Nearly seventy years after the bombings occurred, most of the generation that was
alive during the attack has passed away.
Individuals who had been exposed to radiation before birth, studies, such as one led
by E. Nakashima in 1994, had shown that exposure led to increases in small head
size and mental disability, as well as impairment in physical growth.
After the bomb denotated death was caused immediately, but effects would last for
Radioactive particles were brought by the rain from the fallout of the atomic bomb.
The Japanese people who survived the blast, were affected this way, and more lives
were lost to the effects of radiation poisoning.
The effects from these bombs would continue to pass along in the following
generations. An example of this would be that their children have a high rate of
The first atomic bomb revealed the true destructive power these weapons contain.
This allowed the U.S. to learn and understand atomic bombs. It also helped figure out
the effects they caused.
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