Manhattan Project History

Summary of Target Committee Meetings May 10 and 11, 1945 Declassified government document Memorandum from Major J. A. Derry and Dr. N. F. Ramsey to General L. R. Groves Status of Targets A. Dr. Stearns described the work he had done on target selection. He has surveyed possible targets possessing the following qualifications: (1) they […]

Kenneth Bainbridge: “No one who saw it could forget it, a foul and awesome display.” Enrico Fermi: “About 40 seconds after the explosion, the air blast reached me. I tried to estimate its strength by dropping from about six feet small pieces of paper before, during, and after the passage of the blast wave. Since, […]

The scene inside the shelter was dramatic beyond words. In and around the shelter were some twenty-odd people concerned with last minute arrangements prior to firing the shot.

A PETITION TO THE PRESIDENT OF THE UNITED STATES July 17, 1945 Discoveries of which the people of the United States are not aware may affect the welfare of this nation in the near future. The liberation of the atomic power which has been achieved places atomic bombs in the hands of the Army. It […]

Science Panel’s Report to the Interim Committee June 16, 1945 TOP SECRET RECOMMENDATIONS ON THE IMMEDIATE USE OF NUCLEAR WEAPONS You have asked us to comment on the initial use of the new weapon. This use, in our opinion, should be such as to promote a satisfactory adjustment of our international relations. At the same […]

Report of the Committee on Political and Social Problems Manhattan Project “Metallurgical Laboratory” University of Chicago June 11, 1945   V. Summary The development of nuclear power not only constitutes an important addition to the technological and military power of the United States, but also creates grave political and economic problems for the future of […]

From “Voices of the Manhattan Project,” 2002 interview with Thomas O. Jones I was in my office when the phone rang. Washington was calling, which happened steadily throughout the day. But this was to report that President Roosevelt had just died in Warm Springs. The first thing I had to do was get to Oppenheimer. His office […]

201 Baker, Nicholas, 5 February 1944.   MEMORANDUM FOR:    Dr. R. C. Tolman, Office of Scientific Research & Development, Washington, D. C. Subject: Nicholas Baker. 1. At the conclusion of a recent report of the technical surveillance of the Bakers, the reporting agent made the following comment: “Both the father and son appear to be […]

From “Voices of the Manhattan Project,” 2002 interview with Theodore Rockwell At its peak, the plants at Y-12 had 22,000 workers who ran the “calutrons,” machines designed after the cyclotron or “atom smasher” invented by Ernest O. Lawrence at the University of California. The Y-12 “calutrons” were used to separate the two nearly identical isotopes of uranium. […]

From “Voices of the Manhattan Project,” 2005 Interview with Stirling Colgate Before any of the important visitors arrived, we knew that the decision had been made that this would be a laboratory. About a month or two earlier, a “mega-bulldozer” came through the place and set about redoing things—roads and everything else. The construction work was being […]