Satellite data backs theory of North Korean nuclear site collapse Whether underground cave-ins have made the facility unusable is unknown BY MARIA TEMMING 2:00PM, MAY 10, 2018 A new analysis of satellite images and seismic waves from North Korea’s nuclear test site support theories that the underground facility has at least partially collapsed. Seismologists across the world have been tracking the clandestine nuclear weapons program for years by analyzing vibrations that emanate from explosions at the test site under Mount Mantap (SN: 8/5/17, p. 18). Now, researchers have paired 3-D satellite images of Mount Mantap with seismic tremor data to...