The Navy Space Surveillance System (NavSpaSur) was developed between 1958 and 1964 by the US Naval Research Laboratory (NRL) for the detection and tracking of foreign satellites. Operated by the United States Navy from 1961-2004 and thereafter by the US Air Force until its decommissioning in 2013, the system (known as the Space Fence) had three transmitting sites and six receiving stations across the southern United States. Its radar signals detected active satellites and larger pieces of space debris passing through them at altitudes up to 15,000 miles and helped determine their orbital elements. An improved space surveillance radar on Kwajalein Atoll in the Pacific entered service in 2020.

The Navy Space Surveillance System (NavSpaSur) was developed between 1958 and 1964 by the US Naval Research Laboratory (NRL) for the detection and tracking of foreign satellites. Known as the Space Fence, the system began operations in 1959. Operated by the United States Navy from 1961-2004 and thereafter by the US Air Force until its decommissioning in 2013, the system had three transmitting sites and six receiving stations across the southern United States. Its radar signals detected active satellites and larger pieces of space debris passing through them at altitudes up to 15,000 miles and helped determine their orbital elements. Transmitter sites were located at Lake Kickapoo, Texas (Station SK); Gila River, Arizona (Station SG); and Jordan Lake, Alabama (Station SJ). Receiver stations were located at San Diego, California (Station SS); Elephant Butte, New Mexico (Station SE); Red River, Arkansas (Station SR); Silver Lake, Mississippi (Station SM); Hawkinsville, Georgia (Station SH); and at Fort Stewart (Tattnall County), Georgia (Station ST). Data collected at the receiver stations was transmitted to the NAVSPASUR Headquarters and Computation Center at the Naval Surface Weapons Center, Dahlgren, Virginia. Command of the system was transferred to the US Air Force's 20th Space Control Squadron in October 2004. The Air Force Space Surveillance System (AFSSS) was shut down on September 1, 2013. An improved space surveillance radar on Kwajalein Atoll in the Pacific entered service in 2020.