The Manhattan Project - America's Nuclear Bomb


The Manhattan Project was the code name of a government program to develop an atomic bomb during World War II. Although over 100,000 scientists and engineers worked on the project throughout the USA, the main work was done at the  Los Alamos laboratory in the New Mexican desert. The whole project cost a total of 2 billion dollars.

America’s nuclear program goes back to the year 1939 when German physicist Albert Einstein wrote a letter to American president Franklin D Roosevelt, warning him that Nazi Germany was creating a nuclear weapon. Scientists thought that they could release gigantic amounts of energy by splitting an atom. However large amounts of uranium and plutonium were needed to create such a device.

After Japan had attacked Pearl Harbour in 1941 Roosevelt gave the orders to put together a research group to develop and test a nuclear bomb. In 1942 Enrico Fermi, an Italian who fled from Fascist Italy, conducted the first controlled nuclear chain reaction.

Many nuclear experts, including Canadian and British scientists, started working on an atomic bomb. The American government also sought the help of German  scientists who fled from Nazi Germany.

In 1943 Robert Oppenheimer, leader of the Manhattan Project, chose the the desert at Los Alamos as the place to conduct the project.  Knowledge was kept within the inner circles of the group so that America's enemies did not learn about the project.While most of the research was carried out at Los Alamos, other facilities in the United States produced uranium and plutonium needed for the Manhattan Project.

On June 16, 1945 scientists conducted the first nuclear test about 400 km south of Los Alamos . The gigantic explosion was accompanied by a flash of light, which was visible for many miles,  and a tremendous heat wave . The destructive force of 18,000 kg of dynamite formed a crater that was half a mile wide. A mushroom cloud rose over 12000 metres into the sky.



Almost two months after the successful test later America decided to force Japan to surrender by dropping two nuclear bombs. The first one, a uranium bomb called Little Boy was dropped over Hiroshima on August 6, 1945 .  Three days later, Fat Man, a plutonium bomb destroyed most of Nagasaki.

The Manhattan project helped to end World War II and marked the beginning of the Atomic Age .




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  • although = while
  • amount = how much of something
  • attack = to use guns and bombs against an enemy in a war
  • billion = a thousand million
  • code name = secret name that is used for a project or a person
  • conduct = carry out
  • create = make
  • desert = large are of land where it is always hot and there is not much rainfall
  • destroy = damage completely
  • destructive = causing damage to people or things
  • develop =create, make something new
  • device = object, machine
  • dynamite = powerful explosive used especially for breaking rock
  • enemy = country or people you fight against in a war
  • engineer = someone whose job it is to build things, like roads, bridges, weapons etc..
  • facility = building, used for a special job
  • flee – fled = escape from
  • force = make someone do something
  • force = power
  • gigantic = very large
  • government = the people who rule a country
  • however = but
  • including = also
  • knowledge = information, what you know about something
  • laboratory = special building or house in which a scientist does experiments
  • main = most
  • mark = the sign for
  • mushroom cloud = large cloud shaped like a mushroom, caused by a nuclear explosion
  • nuclear = atomic
  • nuclear chain reaction = action that produces energy and causes more reactions of the same kind
  • physicist = person who has special training in physics
  • plutonium = radioactive metal, used to produce nuclear power and bombs
  • release= set free
  • research = to find out more about a topic or try out new things
  • scientist = person who is trained in science and works in a laboratory
  • seek – sought = ask for
  • split = divide , separate
  • successful = positive; something that worked out well
  • surrender = give up
  • throughout = in all of
  • tremendous = great, huge
  • visible = to be seen
  • weapon = here: bomb