1st (Oct. 9, 2006)Testing material: plutonium
Magnitude of artificial earthquake: 3.9
Explosive power: 1 kiloton
Interval between rocket launch and nuclear test: 33 months
2nd (May 25, 2009)
Testing material: plutonium
Magnitude of artificial earthquake: 4.5
Explosive power: 2-6 kilotons
Interval between rocket launch and nuclear test: 50 days
3rd (Feb. 12, 2013)
Testing material: presumably highly enriched uranium
Magnitude of artificial earthquake: 4.9-5.1
Explosive power: 6-16 kilotons
Interval between rocket launch and nuclear test: two monthsGraphic