This section provides an overview of the history of the Manhattan Project, the key organizations involved, the science behind the bomb, and more.

Oppenheimer Security Hearing

In 1954, J. Robert Oppenheimer's security clearance was revoked by the Atomic Energy Commission.
B Reactor controls.

Peaceful Nuclear Innovations

Nuclear science has many peaceful implications for science and technology.
Plutonium pellet.


Plutonium's discovery in 1941 created unique opportunities and challenges for scientists.
President George H. W. Bush and President Mikhail Gorbachev sign United States/Soviet Union agreements to end chemical weapon production and begin destroying their respective stocks, 1990. Photo courtesy of the George Bush Presidential Library.

Post-Cold War World

The collapse of the Soviet Union in 1989 created a number of problems for the international community with regards to nuclear weapons.
Winston Churchill, Harry Truman, and Joseph Stalin

Potsdam: The Crossroads of Atomic Science and International Diplomacy

The Potsdam Conference was attended by representatives of the United States, the United Kingdom, and the Soviet Union in July 1945.
Project Alberta team members on Tinian

Project Alberta

Project Alberta, also known as Project A, was a division of the Manhattan Project created to plan and carry out all the necessary steps for making the atomic bombs operational.
B29 Superfortess.

Project Silverplate

Project "Silverplate" was the code name for the program to produce a special version of the B-29 capable of delivering the atomic bomb.
Flag at Trinity Site at half-staff in remembrance of Roosevelt

Remembering Franklin Delano Roosevelt

Manhattan Project veterans remember the death of President Franklin Delano Roosevelt.
World War II poster


Protecting workers was an important priority for Manhattan Project officials.