Explosions in 1986

On 26 April 1986, reactor 4 of the Chernobyl Nuclear Power Plant, located near Pripyat, Ukrainian SSR, Soviet Union, exploded. With dozens of direct casualties and thousands of health complications stemming from the disaster, it is one of only two nuclear accidents rated at the maximum severity on the International Nuclear Event Scale, the other being the 2011 Fukushima nuclear accident. The response involved more than 500,000 personnel and cost an estimated 18 billion rubles. It remains the worst nuclear disaster and the most expensive disaster in history, with an estimated cost of US$700 billion.

On January 28, 1986, Space Shuttle Challenger broke apart 73 seconds into its flight, killing all seven crew members. The spacecraft disintegrated about 46,000 feet (14 km) above the Atlantic Ocean, off the coast of Cape Canaveral, Florida, at 16:39:13 UTC. It was the first fatal accident involving an American spacecraft while in flight.

series of U.S. nuclear tests

group of 14 nuclear tests conducted in 1986-1987