Air Force Space Surveillance System transmitter antenna

Previously known as The Naval Space Surveillance network (NAVSPASUR), was operated by Naval Space Command, consists of a series of 216.980 MHz transmitters and receivers which form an electronic "fence" across the southern United States. It extends from Georgia to California (4,800 km), 1,600 km off each coast, and 24,100 km into space. The NAVSPASUR fence provides continuous surveillance and unalerted detection, warning and tracking of low-to-medium orbit space objects.