History

History

This section provides an overview of the history of the Manhattan Project, the key organizations involved, the science behind the bomb, and more.
Photo courtesy of the National Archives and Records Administration

Japanese Balloon Bombs "Fu-Go"

On November 3, 1944, Japan released fusen bakudan, or balloon bombs, into the Pacific jet stream. Japan’s latest weapon, the balloon bombs were intended to cause damage and spread panic in the continental United States.
Japanese resistance fighters captured

Japanese Mass Suicides

The War of the Pacific against Imperial Japan was marked by episodes of mass suicides by Japanese soldiers and civilians, notably in Saipan and Okinawa.
Jumbo on train

Jumbo

Jumbo was designed by Los Alamos lab to act as a failsafe device for the Trinity test explosion.
Leo Szilard. Image courtesy of Argonne National Laboratory.

Leo Szilard's Fight to Stop the Bomb

Hungarian-American physicist Leo Szilard's petition sought to avert use of the atomic bombs against Japan.
Kennedy signs the LTBT

Limited or Partial Test Ban Treaty (LTBT/PTBT)

The Limited Test Ban Treaty (LTBT), also known as the Partial Test Ban Treaty (PTBT), is an arms control agreement intended to restrict the testing of nuclear weapons and limit nuclear proliferation.
Little Boy ready to be lifted into the Enola Gay

Little Boy and Fat Man

Technical description, photographs, and video of atomic bombs Little Boy and Fat Man dropped on Hiroshima and Nagasaki in August 1945.
Los Alamos Ranch School boys playing hockey on Ashley Pond, 1924.

Los Alamos Before World War II

The Pajarito Plateau has been home to a number of inhabitants who have each uniquely shaped the landscape and history of the area.
Your pen and tongue can be enemy weapons

Mail Censorship

Mail censorship was a crucial aspect of the secrecy of the Manhattan Project. Individuals at Los Alamos remember situations where mail censorship disrupted their lives.
Lawrence O'Rourke SAM badge. Courtesy Larry O'Rourke.

Manhattan Project Begins - 1942

The summer of 1942 proved to be troublesome for the fledgling bomb project.

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