North Korea dropped a bomb underground yesterday, conducting its third successful nuclear test since 2006 and creating a small seismic event. The explosion was about twice as large as the last test, in 2009, though the bomb is thought to have been made with plutonium, and not the much scarier uranium. U.S. officials had been expecting such a test, and the president has already issued a statement condemning it—as has China, North Korea's only regional ally—though it likely won't stop North Korea from conducting a fourth test in the coming days. North Korean officials remain unbowed, literally: "The DPRK will never bow to any resolutions," a top diplomat told the Conference on Disarmament.

According to reports from the U.S. Geological Survey, there was a small, 4.9 magnitude earthquake in North Korea late on Monday. The tremor's epicenter was reportedly near North Korea's previous nuclear test sites, where devices were detonated in 2006 and 2009, fueling rumors that the quake was the result of a nuclear explosion. Those rumors have now been confirmed by a United Nations Security Council diplomat, South Korea's Defense Ministry, who are reporting the test yielded an explosion of six to seven kilotons, and the North Korean government.