Radiation at the first Soviet nuclear weapon test site RDS 1
HD The first atomic bomb of Five countries 1945~1964 USSR China UK French USA
RDS-3 Soviet atomic bomb test (1951)
The RDS-1, also known as Izdeliye 501 and First Lightning, was the nuclear bomb used in the Soviet Union's first nuclear weapon test. The United States assigned it the code-name Joe-1, in reference to Joseph Stalin. It was detonated on 29 August 1949 at 7:00 a.m., at Semipalatinsk, Kazakh SSR, after top-secret research and development as part of the Soviet atomic bomb project.