 "North Korea nuclear test, Kim Jong-un, Nuclear tes")
North Korea’s six nuclear tests since 2006 have been part of a program to develop nuclear-tipped missiles that can threaten the U.S. and its allies. Each test has shown progress toward that goal.
Oct. 9, 2006
Magnitude of earthquake: 4.1
Estimated yield of explosion: Less than 1 kiloton
After sporadic multilateral talks with North Korea for years over its nuclear ambitions, the nation exploded a device that was widely viewed as partially successful test of a nuclear bomb.
May 25, 2009
Magnitude of earthquake: 4.7
Estimated yield of explosion: 2-6 kilotons
North Korea’s second nuclear test was viewed by experts
