Radioactivity is measured in Becquerels, which convey the disintegration of an atomic nucleus per second.

FORBES: Major Milestones Passed At The Fukushima Daiichi Nuclear Power Plant

Three days later a second atomic bomb was dropped on Nagasaki, and Japan surrendered unconditionally six days after that.

ECONOMIST: Thomas Ferebee | The

Then there is the Manhattan Project, the name given to America's development of the atomic bomb during the second world war.

ECONOMIST: William Sunderman

The group, which was founded by scientists who had worked on the first atomic bombs in the second world war, listed the continuing crisis between India and Pakistan over the disputed region of Kashmir as one of their concerns.

ECONOMIST: South Asia’s nuclear winter | The

Creating atomic-time standards became a priority in both America and Britain after the second world war.

ECONOMIST: Global positioning: Accuracy is addictive | The

It was announced a day after the second anniversary of the Fukushima earthquake, tsunami and nuclear crisis that crippled the country's atomic power industry and exposed its lack of domestic energy sources.

CNN: Japan warms to 'fire ice' potential