This section provides an overview of the history of the Manhattan Project, the key organizations involved, the science behind the bomb, and more.
A number of scientists associated with the Manhattan Project were eventually investigated by the House Un-American Activities Committee.
In January 1950, President Truman made the controversial decision to continue and intensify research and production of thermonuclear weapons.
How to separate the much more potent U-235 from its abundant relative, U-238 consumed thousands of hours and millions of dollars.
In the aftermath of the attack on Pearl Harbor, President Roosevelt ordered the "evacuation" of Japanese Americans to relocation and internment camps under Executive Order 9066.
Japan initiated multiple small efforts to pursue an atomic bomb, but all were unsuccessful.
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.
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 was designed by Los Alamos lab to act as a failsafe device for the Trinity test explosion.
Hungarian-American physicist Leo Szilard's petition sought to avert use of the atomic bombs against Japan.