21st Space Operations Squadron, Detachment 1 - (Diego Garcia Tracking Station)

Diego Garcia Tracking Station (DGS) or call sign “REEF” is Detachment 1 of the 21st Space Operations Squadron, a unit of Space Delta 6, Space Operations Command, Schriever Space Force Base, Colorado. It is one of the seven worldwide satellite remote tracking stations in the Satellite Control Network (SCN).  


DGS is located on the island of Diego Garcia in the southern portion of the Chagos Archipelago, British Indian Ocean Territory (BIOT), in the Central Indian Ocean. DGS is the only Remote Tracking Station located in the southern hemisphere     ; it is located approximately seven degrees south of the equator. The island itself stretches 15 miles from north to south on the world’s largest unspoiled coral reef system. From the air it takes on the rough outline of a footprint on the ocean surface—thus, its nickname "Footprint of Freedom." 


Following the formation of the BIOT in 1965, a formal agreement signed between the United Kingdom and the United States made Diego Garcia available to satisfy the defense needs of both governments.  Between 1971 and 1988, the military base was constructed and in 1990, Detachment 1 was established in 1991 as the newest RTS in the SCN. After several reorganizations/ redesignations, in 2020 the 21st Space Operations Squadron, Detachment 1 was assigned under Delta 6, Space Operations Command, United States Space Force.

REEF Tracking Station Overview

DGS is a tenant unit on Naval Support Activity Diego Garcia (BIOT). Its mission is to execute on-demand, real-time C2 operations for launch and operations of DoD, allied, and civil satellites providing assured access to space.  DGS supports DoD-assigned space missions by operating and maintaining SCN antennas providing data and status to multiple users and command centers. Additionally, the unit also supports other DoD systems providing critical capabilities in support of the Joint Force in the INDOPACOM region. 

The unit consists of one military member and approximately 20 contractors executing the 24/7 mission enabling real-time satellite C2 in support of the warfighter.  The unit is part of the $6.8 billion SCN.  The SCN ground systems consist of Automated Remote Tracking Station (ARTS), Remote Block Change (RBC), and Hybrid RBC antennas. DGS is a two-sided station comprised of a ten-meter (A-side) hybridized antenna and a 13-meter (B-side) antenna. In 2022 DGS was upgraded to an RBC Hybrid.     

21 SOPS, Detachment 1 SCN Systems


Antenna                                 Transmit                                Receive                        Built

DGS-A RBC Hybrid              1.75 to 1.85 GHz                    2.2 to 2.3 GHz                1991

DGS-B RBC                           1.75 to 1.85 GHZ                    2.2 to 2.3 GHZ                 2009



Key Personnel

Commander                                                    Capt Walid Basraoui



 (Current as of February 2024)