The Comprehensive Nuclear-Test-Ban Treaty Organization recorded some of the first data indicating both the recent Russian meteor hit and the North Korean nuclear test. How’d it know so fast? The organization maintains 337 seismic, hydroacoustic, infrasound and radionuclide monitoring stations all over the world, to catch when someone sets off a nuclear explosion. Although built to monitor nuclear activity, the stations also gather data that can be used for tsunami warnings and for studies about volcanoes, climate change, whale migrations and other science, the organization says. What follows are photos of some of the stations’ coolest locales.