The Development of the Atomic Bomb

1. The decision to build an atomic bomb started on August 2, 1939.

2) At the start of the war, the Germans were making progress towards an Atomic Bomb. They did not know the mechanics but were working on the theory behind it. They had a majority of the best physicists in the world working for them, including Albert Einstein. Many of these physicists were Jewish and once they realized it would be wise to leave Germany, they emigrated to the U.S. Shortly before the bombs were dropped, FDR dies in office. President Truman then takes over. He was in fact the one who ordered the dropping of the Atom Bombs. At the time, the Allies were clearly favored to win, and it was clear from the battles in the pacific that the Japanese would not surrender. It was cornerstone of their culture and personal honor. All Japanese would die fighting rather than surrender. Also, the Japanese had treated American prisoners terribly, torturing them, and sending them on death marches. The U.S. did a calculation whether it was worth the U.S. soldier's deaths that would come from an invasion of the Japanese mainland to save the innocent civilian deaths of the Japanese. They found it was not. For all these reasons, Truman and his Generals felt that the dropping of the two Atom bombs on Hiroshima and Nagasaki was the right course of action. Though at the time we only had two bombs, and it would take us some time to make more, for all the Japanese knew, we had 20 of them, and this helped lead to their unconditional surrender.

3.) The Manhattan Project was well developed by 1942, when Germany was trying to also build an atomic bomb. It was decided that the atomic bomb would be used against Japan, but first we needed to test out the atomic bomb on New Mexico near the desert of Alamogordo. On July 16, 1945 The Atomic Bomb was dropped on a test target in New Mexico for the first trial; this atomic bomb was called "Fat Man."
"Fat Man"

In 1945, as the Allied forces were preparing to invade the Japanese home islands, President Truman gave the command to drop atomic bombs on actual targets in Japan. "Little Boy" was dropped on Hiroshima on August 6th, 1945. The second "Fat Man" was dropped on Nagasaki on August 9th, 1945. These two bombing combined killed over 100,000 people. The goal was for Japan to submit to unconditional surrender. After dropping the second atomic bomb, Japan did surrender without condition on August 15, 1945.
The Allies choose to drop "little boy" on Hiroshima on August 6th because this was where a majority of military camps were located. When the plane was above Hiroshima it dropped the bomb at 1,900 ft above the city, the bomb missed its target, Aioi Bridge, and hit a medical center. The Japanese did not intercept the planes because their radar showed only 3 planes above Hiroshima. They did not suspect that one of the planes was carrying an atomic bomb. The Allies then choose to bomb Nagasaki because it was the city that produced military equipment; the plan was very similar to bombing of Hiroshima. The bombing of Nagasaki was more precise, hitting the target dead. It resulted in more then 40,000 deaths.

Important People that Played Roles in this Event
Though there were many people that contributed to the creation of the atom bombs, here are some of the most influential.

Col. James Marshall- He oversaw the construction of factories to separate uranium isotopes and manufacture plutonium for the bomb for Army Corps of Engineers.

General Leslie Groves- in the Summer of 1942 he was appointed director of the Manhattan Project. He oversaw everything that went on and kept all the scientists in line.

Richard Feynman- In 1942 he was the leader of the theoretical division. Feynman estimated how much uranium would be needed to achieve critical mass, and later developed ways to protect others from radiation poisoning. He later won the 1965 Nobel Prize in Physics.

Rear Admiral William Sterling Parsons- was the Commander of the Hiroshima bombing mission. Earlier, he was the director of the Ordinance Division and associate director of the Los Alamos Laboratory.

Importance of event:
5.) The development of the atomic bomb is very important to our history, if we did not drop the bomb on Hiroshima, we don't know how long the war could have gone on for, and how many more lives would have been lost. The Japanese would have most likely only surrendered at the bitter end if it were not for the two bombs. The dropping of the bombs on Hiroshima and Nagasaki changed the way modern wars were fought forever. They are now always thought of as a last option but will remain a threat forever.

Chemistry behind the Bomb
On the most basic level, Atomic bombs use nuclear fission. This is where enriched uranium, (uranium-235 and 238) is compressed into a supercritical mass by shooting an extra nucleus into the atom, causing a chain reaction, creating hundreds of millions of volts of electricity. This random energy disperses, causing an explosion.

Interesting Fact:
7.) The bomb "Fat Man" was in reference to the prime minister Winston Churchill.