Chernobyl disaster Chernobyl disaster The Chernobyl disaster, also referred to as the Chernobyl accident, was a catastrophic nuclear accident. It occurred on 25–26 April 1986 in the No. 4 light water graphite moderated reactor at the Chernobyl Nuclear Power Plant near the now-abandoned town of Pripyat, in northern Ukrainian Soviet Socialist Republic, Soviet Union, approximately north of Kiev. The event occurred during a late-night safety test which simulated a station blackout power-failure, in the course of which safety systems were intentionally turned off. A combination of inherent reactor design flaws and the reactor operators arranging the core in a manner contrary to
Chernobyl land of Kievan Rus′. The first known mention of Chernobyl is from an 1193 charter, which describes it as a hunting-lodge of Knyaz Rurik Rostislavich. In the 13th century, it was a crown village of the Grand Duchy of Lithuania. The village was granted to Filon Kmita, a captain of the royal cavalry, as a fiefdom in 1566. The province where Chernobyl is located was transferred to the Kingdom of Poland in 1569, and later annexed by the Russian Empire in 1793. Prior to the 20th century, Chernobyl was inhabited by Ukrainian, some Polish peasants and a relatively large number