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Hey, history lovers. I'm Mike Rosenwald with Retropod, a show about the past, rediscovered.

April 25, 1986.

In Previate, a bustling Ukrainian city in the Soviet Union 400 miles from Moscow,

residents were enjoying an unseasonably warm spring day.

And with International Workers Day approaching, the town's laborers, most of them employed

nearby at the Chernobyl nuclear facility, were getting ready to celebrate, stocking up on vodka,

standing in line for meat, planting potatoes. In a matter of hours, disaster would strike.

There has been a nuclear accident in the Soviet Union and the Soviets have admitted that it happened.

One of the atomic reactors at the Chernobyl atomic power plant in the city of Kiev was damaged,

and there is speculation in Moscow that people were injured and may have died.

Whatever did occur there, a radioactive cloud headed north across Poland today and into Denmark.

Disasters don't just happen.

Like anything in life, good or bad, there's usually a buildup.

In the case of the Chernobyl disaster, the series of failures stretched back more than a decade,

including an absurdly misguided decision concerning the reactor's control rods.

Those rods contained boron, a neutron poison, meant to slow down nuclear efficient, reduce power, and thus prevent the reactor

from overheating and exploding. Raising the rods up reduces power, lowering them increases power.

The Soviets, however, wanted to make reactor operation as efficient as possible by making the ends of the rods out of graphite, which didn't slow reactivity.

And in some cases, could cause reactivity in the core to increase.

You can see where this is going.

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