The Chernobyl disaster, also referred to as the Chernobyl accident, was a catastrophic nuclear accident. It occurred on 26 April 1986 in the No.4 light water graphite moderated reactor at the Chernobyl Nuclear Power Plant near Pripyat, in what was then part of the Ukrainian Soviet Socialist Republic of the Soviet Union (USSR).
During a late night safety test which simulated power-failure and in which safety systems were deliberately turned off, a combination of inherent reactor design flaws, together with the reactor operators arranging the core in a manner contrary to the checklist for the test, eventually resulted in uncontrolled reaction conditions that flashed water into steam generating a destructive steam explosion and a subsequent open-air graphite fire.
Pripyat is a ghost town in northern Ukraine, near the border with Belarus.
Named after the nearby Pripyat River, Pripyat was founded on 4 February 1970, as the ninth nuclear city in the Soviet Union, to serve the nearby Chernobyl Nuclear Power Plant. It was officially proclaimed a city in 1979, and had grown to a population of 49,360 by the time it was evacuated, on the afternoon of April 27, 1986, the day after the Chernobyl disaster.
Duga-3 – Soviet experimental over-the-horizon radar system. It was developed for the Soviet ABM early-warning network. Its distinctive and mysterious shortwave radio signal came to be known in the west as the Russian Woodpecker.
Jupiter factory – Prior to the accident the Jupiter factory was a branch of the Kyiv manufacturer “Mayak” and made electrical components, mainly for use in tape recorders. Rumours abound of a military connection and given the nature of the defence industry at that time it is very possible there is truth in this. Following the disaster in 1986 the factory housed radiology laboratories used to test decontamination techniques and dosimetry equipment. The laboratories functioned up until 1996 at which point the factory was abandoned for good.