The Chernobyl Disaster
The world's worst nuclear reactor disaster occurred at the Chernobyl Power Station in the USSR (now Ukraine) on April 26, 1986. Thirty-one people died at the time, and 28,200 sq. km.(10,900 sq. miles) of land and 1.7 million people were exposed to radiation. During a routine test, reactor number 4 was operating on very low power, which made it unstable due to the reactor’s design. A sudden surge of power resulted in two explosions, which wrecked the reactor core and blasted a hole in the roof of the power station. It's not known how many of the estimated 200,000 people involved in the clean-up operation died in the following the disaster, as no systematic records were kept.