Ukraine ousted Khrushchev and became the Soviet leader from 1964 to 1982. Many prominent Soviet sports players, scientists, and artists came from Ukraine. On 26 April 1986, a reactor in the Chernobyl Nuclear Power Plant exploded, resulting in the Chernobyl disaster, the worst nuclear reactor accident in history. This was the only accident to receive the highest possible rating of 7 by the International Nuclear Event Scale, indicating a "major accident", until the Fukushima Daiichi nuclear disaster in March 2011. At the time of the accident, 7 million people lived in the contaminated territories, including 2.2 million in Ukraine. After the
British nuclear testing in the United States powerful conventional explosive, EDC11. The result was that the yield was less than Tsetse, and too small to be used as the primary in the Skybolt warhead. A follow-up test of what became the basis for the WE.177 design codenamed Tendrac therefore took place on 7 December 1962, and was judged a success. Subcritical tests were tests with nuclear weapons that did not involve a nuclear explosion. Safety tests involved testing the impact of fire, shock and other accidents against live nuclear weapons. These did not intentionally involve nuclear explosions, although there was always a danger. Tim subcritical tests and