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
Peaceful nuclear explosion envisaged making two such beams collide in the form of a supercollider. Underground nuclear explosive data from peaceful nuclear explosion test shots have been used to investigate the composition of Earth's mantle, analogous to the exploration geophysics practice of mineral prospecting with chemical explosives in "deep seismic sounding" reflection seismology. Project A119, proposed in the 1960s, which as Apollo scientist Gary Latham explained, would have been the detonating of a "smallish" nuclear device on the Moon in order to facilitate research into its geologic make-up. Analogous in concept to the comparatively low yield explosion created by the water prospecting (LCROSS)