At 2:46 p.m. on March 11, 2011, a 9-magnitude megathrust earthquake triggered a tsunami that slammed into the aging Fukushima No. 1 nuclear power plant along the country's northeastern coastline, less than 250 km north of the capital. In the worst nuclear accident since Chernobyl, the plant's power systems failed, causing cooling units to shut down and sending reactor cores into meltdown.

Fukushima: The Story of a Nuclear Disaster, by David Lochbaum, Edwin Lyman, Susan Q. Stranahan and The Union of Concerned Scientists