The nuclear bomb was the most devastating weapon ever created by man. It was developed between 1942 and 1945 during the second World War. The project to build the worlds first atomic weapon was called The Manhattan Project. The nuclear bomb was based on the idea of splitting an atom to create energy, this is called fission. Three bombs were created, “Trinity”, “Little Boy”, and “Fat Man”. “Trinity” was dropped on a test site in New Mexico on July 16, 1945, proving the theories, engineering and mathematics of the bomb to be correct. Shortly after that, not more than 2 months, the U. S. formed the first actual nuclear attack in the history of war.
The bomb “Little Boy” was dropped on the town of Hiroshima, instantly killing thousands. “Fat Man” was dropped shortly after on the town of Nagasaki. After the bombing almost all scientist involved with the creation of the bomb regretted its construction and spoke out against the abolishment of nuclear weapons. The Manhattan Project was led by American physicists J. Robert Oppenheimer and directed by General Leslie Graves. The project employed over 130,000 people and the total cost by the end of production was nearly 2 billion dollars, 20 billion dollars in today’s currency.
Oppenheimer’s early education was at the Ethnical Culture School in New York. He took classes in math and science and many languages such as Greek, Latin, French, and German. He learned Dutch in only six weeks to give a speech in the Netherlands. He was also interested in classic and eastern philosophy. In 1939 rumor came to the U. S. that Germans had split the atom. The threat of the Nazis developing a nuclear weapon prompted President Roosevelt to establish The Manhattan Project. Oppenheimer set up a research lab in Los Alamos, New Mexico and brought the best minds in physics to work on the problem of creating a nuclear weapon.
Although most the research and development was done in Los Alamos, there were over 30 other research locations throughout the project. After watching the first nuclear bomb test Oppenheimer was quoted as saying simply “It works. “. Now that the atomic bomb was proven to work the next question was where to drop it. Specialists in many fields were called on by the U. S. Army to help them decide on the best target for the atomic bomb. They considered many things while selecting the target such as the range the aircraft had to carry the bomb, the morale effect on the enemy, military importance of the target, and the geography of the target.
The Army also wanted to be able to see the bombing take place (“visual bombing”) so the weather conditions had to be almost perfect, they wanted to witness the effects of the weapon. They also looked for closely built wooden frame structures that were easily susceptible to fire since the blast was expected to be the leading cause of damage while fire was to be second. The scientists in the Manhattan Project expected the blast radius to be around 1 mile therefore the target should have a densely built up area of that size.
Also considered was the damage done by previous bombings, the target should have minimal damage by previous bombings so the effects of the bomb could be more accurately measured. After long analysis the Army chose Hiroshima and Nagasaki as the best possible targets. The city of Hiroshima is almost entirely flat, just above sea level and located on the Ota river. This was the perfect target geographically since it is flat and fully exposed to the blast from the bomb. Seventy-five percent of the population were jammed into a densely built area at the center of the city. Hiroshima was a highly important military target.
The Japanese 2nd Army was headquartered there, this commanded all Japanese defense in southern Japan. The city was also a communications center, storage point and troop assembly area. Outside the center of town the area was packed with small wooden workshops and wooden houses. Most industrial buildings in the area were also built with wooden frame construction. This made the city as a whole highly susceptible to fire. The population in Hiroshima had a peak of 380,000 but at the time of the bombing the population is suspected to be around 255,000 or approximately the same number of people that occupy Dallas, Texas.
At about 8:15 a. m. on Monday, August 6th, 1945, “Little Boy” was dropped on the city of Hiroshima. It exploded at a height of 2,000 feet. The bomb was dropped by a plane by the name of the Enola Gay. Co-pilot Robert Lewis reported that after the explosion he could taste the nuclear fission, he said that it tasted like lead. The damage from just the blast alone was horrific. At the moment of the explosion a super-high air pressure of several thousand atmospheres was created. This generated a powerful shockwave and the wind blew at about 1000 miles per hour.
Thousands were killed by being thrown through the air or crushed by structures. The blast shattered windows sending glass flying through the air, penetrating deep into the victims bodies. The blast was so powerful that all buildings within 2 kilometers of the hypocenter collapsed, some concrete buildings also collapsed. Another damaging factor of the bomb was heat rays. Within one second of detonation a fireball 280 meters in diameter was created. The temperature on the ground rose to 5,000 degrees Celsius. The powerful heat burned any exposed human skin up to 3. 5 kilometers from the center of detonation.
Anyone unfortunate enough to be within 1. 2 meters of the hypocenter received burns not only on the skin but deep into their bodies and on internal organs. These people died instantly or within days. Roof tiles melted and some fences ignited. The heat rays emitted by the explosion caused any burnable building in the downtown area to burst into flames. Any combustible material within 2 kilometers of the explosion was burned to ash and cinders. The heat melted glass and metal. When the flames died off there was nothing left but scorched plain. The final damage from the bomb was dealt in radiation.
Given that a person exposed to 4 “grays” of radiation dies, anyone within 1 kilometer of the explosion died from initial radiation. Besides the initial radiation, acute radiation effects lasted long after the bombing. Some effects of acute radiation are: destruction of cells, disorders in internal organs, lowered immune function and loss of hair. Within 20-30 minutes of the explosion a thick black rain started falling in the northwest. The rain contained radioactive soot and dust. This contaminated areas far away from the center of explosion. Fish died in ponds and rivers and people who drank well water had diarrhea for about 3 months.
High levels of residual radiation remained on the ground for a long time affecting many people that didn’t even experience the bombing. The effects of radiation lasted decades. Keloids are one of the after effects of radiation. They are scar tissue covering apparently healed burns that begin to swell and grow into mounds of thick twisted flesh. Keloids death great physical and emotional pain. Many victims exposed to high levels of radiation suffered from leukemia. Leukemia onset was about 7-8 years after exposure. Beginning in the 1960’s incidences of cancer began to increase.
Cancers such as thyroid, breast, and lung were most common. The victims distance from the hypocenter effected the probable dose and malignancy rates. The atomic bomb caused many effects on the world, and on the people who witnessed it. Since the bombings of Hiroshima and Nagasaki there has been no further use of atomic weapons on humans. Some believe the bombings were necessary while others believe they were an inexcusable act of mass murder. Regardless, the bombs will be forever remembered as both an amazing feat of human engineering and as destructive weapons which have no rival in power.