The explosion took place near Kilju, in North Korea. Seismic waves were recorded by a station in Mudanjiang, China, 205 miles north. That is the closest station with data civilian researchers can get access to in real time. | Courtesy Won-Young Kim, Lamont-Doherty Earth Observatory

North Korean Nukes Getting Bigger

Data from a seismic station in China confirms that North Korea is getting a lot better at building nuclear bombs. The good news: they can't hide their tests from seismologists.

February 16, 2013
12:12 PM EST


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