The listening stations were the nation's first line of detection for nuclear explosions worldwide. The four arrays of listening stations operated by Los Alamos are the only infrasonic network left in full-time operation in the world. They can detect meteors that are as small as a few centimeters in diameter. The stations are useful because they can help validate other non-proliferation and verification techniques, and they cost very little to operate and maintain. Each year a number of large meteors enter the atmosphere and are detected by the Los Alamos array.
Some meteors are tens of meters in diameter.
Most burn up or explode in brilliant flashes. Some hit the ground. Los Alamos National Laboratory is operated by the University of California for the U.S. Department of Energy.