North Korea Conducted New Nuclear Test

North Korea has successfully made a 6th nuclear test, causing the equivalent of a 6.3 magnitude earthquake. (More from CNN, Deutsche Welle, and the BBC). North Korea is claiming that it was a hydrogen bomb (thermonuclear weapon) that can be mounted on an ICBM. Last year, North Korea had tested a 10 kiloton device which caused a 5.3 magnitude tremor, which suggests that this device was must more powerful. (The tremor from this test is 10x the power of that from last year, suggesting a 100 kt explosion, which is still a short of the power of a thermonuclear weapon).