Seismograph Wikimedia CommonsWhen North Korea tests a new nuclear weapon, seismographs are the first to know. Early Tuesday morning, the United States Geological Survey (USGS) data detected a 5.1 magnitude earthquake in North Korea. Within minutes, night owl commenters like Jeffrey Lewis of the Arms Control Wonk in the U.S. were already discussing the political implications of Kim Jong-Un's first nuclear test. How did seismic readings become key to tracking clandestine nuclear tests? Let's look at a little bit of history. In the beginning of the atomic age, nuclear weapons were tested ... Read More