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The Theory of Nuclear Fission is developed
-German Chemists; Lise Meitner, Otto Hahnand and Fritz Strassmann; develop theoretical explanation of Nuclear fission.
-This makes the development of an atomic bomb possible.
-Otto Hahn and Fritz Strassmann were awarded the Nobel prize for this, but Meitner was left out. BOOOO -
Einstein-Szilard letter sent to Roosevelt
-Hungarian physicist Leo Szilard realizes the possibility of the nuclear chain reaction.
-He drafts a letter to US president, Roosevelt, known as the Einstein-Szilard letter.
-The letter warned of the potential development of extremely powerful bombs of a new type.
-It urged the United States to take steps to acquire stockpiles of uranium ore and accelerate the research of Enrico Fermi. -
Advisory Committee on Uranium set up
-Roosevelt called on Lyman Briggs of the National Bureau of Standards to head the Advisory Committee on Uranium to investigate the issues raised by Einstein-Szilard letter.
-The committee reported back to Roosevelt that uranium would provide a possible source of highly destructive bombs. -
World War II begins
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Office of Scientific Research and Development (OSRD) established
-Roosevelt creates the OSRD, under Vannevar Bush, which absorbs the Uranium Committee.
-The establishment of this government organization begins major research into nuclear fission using uranium -
FDR gives the go-ahead for the development of an atomic weapon
-This is an image of Roosevelt signing a literal "OK" to Vannevar Bush. Bush wrote this letter asking for expansion of the OSRD's fission research.
-With Roosevelt's approval, nuclear fission research is officially channeled into weapons development.
-Lots of money channeled into the project
-Special war-time declarations given to project -
Bombing of Pearl Harbor
The United States and Great Britain issue a formal declaration of war against Japan the next day. -
Manhattan Engineering District is established
-This is where namesake Manhattan Project originated.
-A portion of the MP was originally based on the 18th floor of an office building at 270 Broadway in Manhattan.
-The Army Corps of Engineers worked out of this building.
-New York City was peppered with physics laboratories, including a major one at Columbia University.
-Much of the United States’ stockpile of uranium ore was in NYC warehouses -
Col. Leslie Groves in charge of the Army sector of the Manhattan Project
-Responsibility for developing an atomic bomb was moved from the Office of Scientific Research and Development to the military. -
Robert Oppenheimer becomes the Manhatten Project's scientific director
-He is credited as the "Father of the Atomic Bomb"
-Throughout the Project, he conducts his scientific research at the Site Y laboratory, in Los Almos, New Mexico. -
Manhattan Project Expansion
-At this point, MP was moving to more remote/secure sites to conduct research.
-There were sites in WA, NM, IL, TN -
Enrico Fermi produces the first controlled nuclear fission reaction
-Conducted at University of Chicago
-Fermi is know as the "Father of the Nuclear Age." He is the first person to develop a nuclear reactor.
-The self sustaining reaction was created just one month into the construction of Fermi's nuclear reactor. -
"Thin Man" gun-type fisson bomb developed
-First drop test of this weapon at Dahlgren Proving Ground in Virginia
-Used plutonium, which proved to be impractical with gun-type bombs -
Japan becomes the primary target for any future atomic bomb
After the ramping up of American involvement in WWII, Japan becomes a clear enemy. This prompts a strong reaction and the possible first use of a developing nuclear bomb. -
Roosevelt and Churchill sign Quebec Agreement
-Britain's Tube Alloys is merged with the Manhattan project
-This brings substantial fission research conducted in Britain to America's Manhattan project.
-Britain had made a lot more progress in developing nuclear fission for weapons at this point
-Ally-ship between US and Britain shifted nuclear weapons development into high gear -
"Little Boy" gun-type fission bomb developed
-This fission bomb used uranium-235.
-This was a gun-type bomb
-Uranium proved to work better for gun-type fission bombs -
"Fat Man" bomb developed
-This is a more complex implosion-type nuclear weapon, compared to gun-type uranium bombs.
-Uses Plutonium -
Harry Truman is named the 33rd president of the U.S
Truman replaces Roosevelt -
The world's first atomic detonation takes place
-Conducted as the Trinity Test at Alamogordo, New Mexico
-An implosion-style plutonium-based nuclear weapon is set off--> same design as "Fat Man" bomb
-Test overseen by Oppenheimer -
Potsdam Declaration issued
-This declaration sought the surrender of Japan and threatened destruction otherwise.
-Issued by President Harry S. Truman, United Kingdom Prime Minister Winston Churchill, and President of China Chiang Kai-shek
-Leaflets were dropped by bombers to Japanese citizens outlining terms.
-The declaration was never transmitted to the Japanese government by diplomatic channels -
"Little Boy" uranium bomb is dropped on Hiroshima, Japan
It kills between 90,000 and 100,000 people immediately. -
"Fat Man" bomb is dropped on Nagasaki, Japan
This bomb was originally going to be dropped on Kokura, Japan. It was changed to Nagasaki because of the weather obscuring the original city. -
Atomic Energy Act of 1946
-Determined how the United States would control and manage the nuclear technology
-The Act ruled that nuclear weapon development and nuclear power management would be under civilian, rather than military control. -
Manhattan Project turned over
The United States Atomic Energy Commission now in charge of all technology developed under the Manhattan Project
