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atomic bomb




A weapon of mass destruction deriving its energy from nuclear fission. The first atomic bomb was exploded at Alamogordo, New Mexico, on July 16, 1945. As in the case of the bomb dropped over Hiroshima, Japan, a few weeks later (August 6), the fissionable material was uranium-235. However, when Nagasaki was destroyed by another bomb three days after that plutonium-239 was used. Together the Hiroshima and Nagasaki bombs killed more than 100,000 people. Since the early 1950s, the power of the fission bomb (equivalent to some 20,000 tons of TNT in the case of the Hiroshima bomb) has been vastly exceeded by that of the hydrogen bomb which depends on nuclear fusion.


Nuclear powers

Today, the official nuclear powers are:
  • United States of America (USA) 1945
  • Union of Soviet Socialist Republics (USSR) 1949
  • United Kingdom (UK) 1952
  • France 1960
  • People's Republic of China (PRC) 1964
  • India 1974
  • Pakistan 1998
Additionally, North Korea detonated a few small nuclear explosions in 2006.
The dates refer to the first nuclear detonations.


Related category

   • ATOMIC AND NUCLEAR PHYSICS