“The monitoring system is a latticework of sensors — including radiation detectors and machines that measure seismic activity or low-frequency sound waves — spread out across 89 countries as well as the oceans and polar regions. Like a giant stethoscope, it listens for irregularities in Earth’s natural rhythms, collecting and transmitting terabytes of data to a small office in the Austrian capital.”
Source: Surveillance network built to spot secret nuclear tests | GulfNews.com
