In which month and year did the Fukushima Daiichi nuclear disaster occur?

What natural event directly triggered the Fukushima Daiichi nuclear crisis?

How many reactors at Fukushima Daiichi experienced meltdowns after the March 2011 disaster?

What was the approximate magnitude of the earthquake that preceded the Fukushima tsunami?

What critical safety system failed at Fukushima Daiichi when the tsunami struck?

How large was the mandatory evacuation zone established around Fukushima Daiichi immediately after the disaster?

Which radioactive element released during the Fukushima disaster has a half-life of about 30 years and posed long-term contamination risks?

What emergency measure did workers use to try to cool the reactors when normal systems failed?

On what international scale was the Fukushima disaster rated alongside Chernobyl?

What ongoing challenge has Japan faced in managing contaminated water at the Fukushima site?