190828-F-NI989-0019 Air Force Master Sgt. Jonathon Beedham, 709th Technical Maintenance Squadron, Detachment 421 superintendent, reviews technical data on a seismic array in the outback of Alice Springs, Australia, Aug. 28, 2019. The detachment maintains 20 sensors spread over 100 square kilometers (38.6 square miles) that can detect earthquakes or nuclear detonations through vibrations in the Earth’s crust. SHARE IMAGE: Download Image: Full Size (4.36 MB) Photo By: Air Force Master Sgt. Benjamin Wilson VIRIN: 190828-F-NI989-0019.JPG Photo Gallery