Soviet Union hydrogen bomb tested

Teller was thus back at weapons work when Harry Truman announced, on September 23, 1949, the explosion of Joe I, the first Soviet atomic bomb. Like most Americans, Teller had not expected the Soviet success so soon. He called Oppenheimer on the day the Soviet test was announced in a state of arousal sufficient to cause Oppenheimer to advise him sharply, Keep your shirt on. He testified later that his mind did not immediately turn in the direction of working on the thermonuclear bomb, but in fact he discussed that prospect intensely at Los Alamos early in October with Ernest Lawrence and Luis Alvarez, who encouraged him. The American nuclear monopoly had ended. The fabulous monster had real claws. If the Soviet Union had tested an atomic bomb, could a Soviet hydrogen bomb be far behind Teller decided that the only possible hope for continued national security was an all-out American effort to build the Super. 

The Soviet Union exploded a device with a small hydrogen component in August 1953. Its yield was probably several hundred kilotons, about half the yield of the largest fission weapon the United States had tested up to that time. This was not a true H-bomb, Hans Bethe comments, as I know very well because I was chairman of the committee analyzing the Russian [fallout]. ... 

SEMIPALATINSK. Now located in Kazakhstan, Semipalatinsk was the principal nuclear weapon test site of the Union of Soviet Socialist Republics (USSR). It was established in accordance with a 1947 decision by the Soviet Communist Party s Central Committee and the Council of Ministers. The USSR detonated its first nuclear weapon there on 29 August 1949 under the scientific direction of Igor V. Kurchatov. It was also the site where the USSR detonated its first thermonuclear weapon (12 August 1953) and its first hydrogen bomb (22 November 1955). A total of 467 nuclear weapons were detonated at Semipalatinsk firom 1949 to 1990. The test facility was shut down in 1991. The site is today occupied by the National Nuclear Center of the Republic of Kazakhstan. The region has experienced serious environmental and human health damage as a result of the nuclear weapon tests. See also JOE. 

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