U.S. Intelligence and the Detection of the First Soviet Nuclear Test, September 1949
Washington, DC, September 22, 2009 - Sixty years ago this week, on 23 September 1949, President Harry Truman made headlines when he announced that the Soviet Union had secretly tested a nuclear weapon several weeks earlier. Truman did not explain how the United States had detected the test, which had occurred on 29 August 1949 at Semipalatinsk, a site in northeastern Kazakhstan. Using declassified material, much of which has never been published, this briefing book documents how the U.S. Air Force, the Atomic Energy Commission, and U.S.