The Satellite Control Network (SCN), operated by the

United States Space Force The United States Space Force (USSF) is the space service branch of the U.S. Armed Forces, one of the eight U.S. uniformed services, and the world's only independent space force. Along with its sister branch, the U.S. Air Force, the Space ...

Space Delta 6 Space Delta 6 (DEL 6) is a United States Space Force unit which assures access to space through the $6.8 billion Satellite Control Network and defensive cyberspace capabilities for space mission systems. Activated on 24 July 2020, the delta is ...

, provides support for the operation, control, and maintenance of a variety of

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and some non-DoD

satellite A satellite or artificial satellite is an object intentionally placed into orbit in outer space. Except for passive satellites, most satellites have an electricity generation system for equipment on board, such as solar panels or radioi ...

s. This involves continual execution of Telemetry, Tracking, and Commanding (TT&C) operations. In addition, the SCN provides prelaunch checkout and simulation, launch support, and early orbit support while satellites are in initial or transfer orbits and require maneuvering to their final orbit. The SCN provides tracking data to help maintain the catalog of space objects and distributes various data such as satellite ephemeris, almanacs, and other information. It was previously known as the Air Force Satellite Control Network (AFSCN) while under

Air Force Space Command The atmosphere of Earth is the layer of gases, known collectively as air, retained by Earth's gravity that surrounds the planet and forms its planetary atmosphere. The atmosphere of Earth protects life on Earth by creating pressure allowing for ...

's 50th Network Operations Group.

Overview

The Satellite Control Network consists of satellite control centers, tracking stations, and test facilities located around the world. Satellite Operations Centers (SOCs) are located at

Schriever Space Force Base Schriever Space Force Base, previously Schriever Air Force Base, Falcon Air Force Base, and Falcon Air Force Station, is a base of the United States Space Force located approximately east of Peterson Space Force Base near Colorado Springs in ...

near Colorado Springs, Colorado, and various other locations throughout the

continental United States The contiguous United States (officially the conterminous United States) consists of the 48 adjoining U.S. states and the Federal District of the United States of America. The term excludes the only two non-contiguous states, Alaska and Hawaii ...

. These SOCs are staffed around the clock and are responsible for the command and control of their assigned satellite systems. The SOCs are linked to remote tracking stations (RTSs) around the world. Space vehicle checkout facilities are used to test launch vehicles and satellite platforms to ensure that the onboard systems operate within specifications. The RTSs provide the link between the satellites and the SOCs. A similar relationship exists for dedicated networks, which are outside the purview of the Satellite Control Network. RTSs around the world are needed to maintain frequent communications with the satellite. Without RTSs, the SOCs would only be able to contact a satellite when it came into the control center's view. Some satellites, especially those in geostationary orbit, never come within view of their control center. Each antenna at an RTS is referred to as a "side". Previously, Side A typically included a dish antenna. Side B typically included a antenna. At some sites, the B side included a antenna. Over time, however, as the network upgraded and/or replaced the antennas, the old conventions no longer apply.

History

The Satellite Control Network was originally activated to support the

CORONA Corona (from the Latin for 'crown') most commonly refers to: * Stellar corona, the outer atmosphere of the Sun or another star * Corona (beer), a Mexican beer * Corona, informal term for the coronavirus SARS-CoV-2, which causes the COVID-19 di ...

(Discoverer) program in 1959. An interim satellite control center was initially established in

Palo Alto, California Palo Alto (; Spanish for "tall stick") is a charter city in the northwestern corner of Santa Clara County, California, United States, in the San Francisco Bay Area, named after a coastal redwood tree known as El Palo Alto. The city was es ...

, and by June 1960, a permanent control center had been established Sunnyvale AFS, later renamed Onizuka AFS, Sunnyvale, California. The main operations control center, now at

Colorado Springs, CO Colorado Springs is a home rule municipality in, and the county seat of, El Paso County, Colorado, United States. It is the largest city in El Paso County, with a population of 478,961 at the 2020 United States Census, a 15.02% increase since ...

, functions as a central

command and control Command and control (abbr. C2) is a "set of organizational and technical attributes and processes ... hatemploys human, physical, and information resources to solve problems and accomplish missions" to achieve the goals of an organization or en ...

node for the remote tracking stations established at several different locations.

Locations

Colorado Colorado (, other variants) is a state in the Mountain states, Mountain West subregion of the Western United States. It encompasses most of the Southern Rocky Mountains, as well as the northeastern portion of the Colorado Plateau and the wes ...

– Primary C2 Node * Ellison Onizuka Satellite Operations Facility (EOSOF) at

Vandenberg Space Force Base Vandenberg Space Force Base , previously Vandenberg Air Force Base, is a United States Space Force Base in Santa Barbara County, California. Established in 1941, Vandenberg Space Force Base is a space launch base, launching spacecraft from ...

, California – Secondary C2 Node. The Satellite Control Network maintains a number of tracking stations, which are used to track (primarily) US government agency & military satellites, as well as receive and process telemetry and send commands to these satellites. Said facilities are intended to support all

Department of Defense Department of Defence or Department of Defense may refer to: Current departments of defence * Department of Defence (Australia) * Department of National Defence (Canada) * Department of Defence (Ireland) * Department of National Defense (Philipp ...

satellites. Most tracking stations are operated by operational detachments of the

21st Space Operations Squadron The 21st Space Operations Squadron (21 SOPS) is a satellite control unit of the Space Delta 6 of the United States Space Force, located at Vandenberg Space Force Base, California. Prior to July 2020, it was part of the 50th Network Operations G ...

(21 SOPS) and 23d Space Operations Squadron. Many scientific and research satellites are supported as well.

Current Remote Tracking Stations

* Diego Garcia Station (DGS),

Diego Garcia Diego Garcia is an island of the British Indian Ocean Territory, a disputed overseas territory of the United Kingdom. It is a militarised atoll just south of the equator in the central Indian Ocean, and the largest of the 60 small islands of ...

, BIOT; callsign REEF. The Diego Garcia Station has two sides (as of 2010) to provide enhanced tracking for the Satellite Control Network users. This site also includes a GPS Ground Antenna site. * Guam Tracking Station (GTS),

Guam Guam (; ch, Guåhan ) is an organized, unincorporated territory of the United States in the Micronesia subregion of the western Pacific Ocean. It is the westernmost point and territory of the United States (reckoned from the geographic cent ...

; callsign GUAM. The Guam Tracking Station has two sides (one ARTS and one RBC) and is undergoing a "hybridization" upgrade that replaces the old A-side ARTS system with an RBC core electronics suite and upgrades the existing 60-foot antenna. * Hawaii Tracking Station (HTS), Kaena Point Satellite Tracking Station, Hawaii; callsign HULA. The Hawaii Tracking Station is located on the island of Oahu and also includes an ARTS side and an RBC side. The Hawaii Tracking Station is also undergoing a "hybridization" effort that will replace the old B-side ARTS system and upgrade the existing 60-foot antenna (previously the A-side). * New Hampshire Station (NHS), New Boston SFS,

New Hampshire New Hampshire is a state in the New England region of the northeastern United States. It is bordered by Massachusetts to the south, Vermont to the west, Maine and the Gulf of Maine to the east, and the Canadian province of Quebec to the nor ...

; callsign BOSS. The

Tracking Station is located in New Boston,

. As of 2013, the site had two ARTS sides and an RBC side. * Telemetry & Command Station (TCS),

RAF Oakhanger RAF Oakhanger is a Royal Air Force station in Hampshire split over three operational sites; with accommodation in nearby Bordon. The main site and operations centre is located near the village of Oakhanger, the two other sites being nearby. Th ...

, in England, operated by the United Kingdom and supporting the Satellite Control Network through a Memorandum of Agreement between the UK Ministry of Defence and the US Department of Defense; callsign LION. As of 2010, the site includes three sides, two ARTS and an RBC. * Thule Tracking Station (TTS),

Thule Air Base Thule Air Base (pronounced or , kl, Qaanaaq Mitarfik, da, Thule Lufthavn), or Thule Air Base/Pituffik Airport , is the United States Space Force's northernmost base, and the northernmost installation of the U.S. Armed Forces, located north ...

, Greenland; callsign POGO. The station ) is a

U.S. Space Force The United States Space Force (USSF) is the space service branch of the U.S. Armed Forces, one of the eight U.S. uniformed services, and the world's only independent space force. Along with its sister branch, the U.S. Air Force, the Space ...

installation in

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. It is near

and has a Remote Tracking Station (callsign: Polar Orbiting Geophysical Observatory (POGO)) of the Satellite Control Network. It was originally the classified 6594th Test Wing's Operating Location 5 designated by Air Force Systems Command on 15 October 1961: the station was operational on 30 March 1962, with "transportable antenna vans parked in an old Strategic Air Command bomb assembly building." The permanent RTS equipment was emplaced in 1964, and a communications terminal was emplaced on Pingarssuit Mountain—Thule Site N-32 (moved to

Thule Site J Thule Site J (J-Site) is a United States Space Force (USSF) radar station in Greenland near Thule Air Base for missile warning and spacecraft tracking. The northernmost station of the Solid State Phased Array Radar System, the military installa ...

in 1983. The station transferred to Detachment 3,

22nd Space Operations Squadron The 22d Space Operations Squadron is a satellite control unit of the United States Space Force. It is part of Space Delta 6 and is located at Schriever Space Force Base, Colorado. Prior to July 2020 it was part of the 50th Network Operations Gr ...

, in 1992. It includes a "fully equipped mini-fitness center". It was a three-sided site until the summer of 2011, when the "C" side was decommissioned and dismantled in preparation for system upgrades. The upgrade to an

Automated Remote Tracking Station Automation describes a wide range of technologies that reduce human intervention in processes, namely by predetermining decision criteria, subprocess relationships, and related actions, as well as embodying those predeterminations in machines ...

was planned to be completed in 2015. In May, 2013, the A-side antenna suffered a mechanical failure that prompted an early decommissioning. From that time, the site operated only with its B-side. Starting in 2014, the new C-side RBC installation got under way. This is the northernmost RTS, located at approximately 76.4 degrees north latitude. As of February 2015, the RBC installation is nearly complete, with just a few minor details to be finished before the formal testing gets underway in the May/June timeframe. * Vandenberg Tracking Station (VTS), California; callsign COOK. This is a dual-sided station which provides normal on-orbit support but also provides pre-launch checkouts and launch support for the

Western Test Range The Western Range (WR) is the space launch range that supports the major launch head at Vandenberg Space Force Base. Managed by the Space Launch Delta 30, the WR extends from the West Coast of the United States to 90° East longitude in the ...

Automated Remote Tracking Stations

In the late 1980s and early 1990s, the RTSs were modernized with the addition of the Automated Remote Tracking Station (ARTS) systems. The ARTS systems provided more responsive support and reduced the manpower required at each site through semi-automation. In addition to upgrading all the existing sites, the ARTS Phase I program added the following sites to the Satellite Control Network: *Colorado Tracking Station at Schriever Air Force Base, Colorado, which had a "cessation of operations" in August 2012 and was formally deactivated in 2014 *Thule Tracking Station "C" side, which was decommissioned in 2011 and dismantled that summer *Telemetry and Command Station "B" side *Diego Garcia Station "A" side

RTS Block Change (RBC) Systems

Beginning in 2004, an upgrade effort was started to replace the ARTS sites, which were already beyond their planned design life. The following sites have been upgraded to the RBC configuration, which includes a 13-meter 3-axis antenna: *Vandenberg Tracking Station "A" side *Diego Garcia Station "B" side, added to the network during the upgrade effort *Telemetry and Command Station "C" side, added to the network during the upgrade effort *Hawaii Tracking Station "A" side *Guam Tracking Station "B" side *New Hampshire Station "B" side *Thule Tracking Station "C" side

Closed Remote Tracking Stations

*Indian Ocean Station (IOS), Mahe Island, Seychelles; callsign INDI (closed in August 1996, after the Government of Seychelles attempted to "raise the rent" to more than $10 million/year). The Indian Ocean Tracking Station was located on the island of Mahe, the main island of the Seychelles archipeligo. It had one 60-foot antenna. Its location was ideal for communicating with geosynchronous satellites over the Indian Ocean. The station was also geographically suited for acquiring realtime or near-realtime data from passes over areas to the north. In 1980, due to political instabilities of the island, the main processing computers were removed and relocated to Sunnyvale. These computers communicated with the IOS downlink and tracking equipment via a wideband (DSCS) communications link. IOS has been supplanted by Diego Garcia RTS. *Kodiak Tracking Station (KTS),

Kodiak Island Kodiak Island ( Alutiiq: ''Qikertaq''), is a large island on the south coast of the U.S. state of Alaska, separated from the Alaska mainland by the Shelikof Strait. The largest island in the Kodiak Archipelago, Kodiak Island is the second la ...

Alaska Alaska ( ; russian: Аляска, Alyaska; ale, Alax̂sxax̂; ; ems, Alas'kaaq; Yup'ik: ''Alaskaq''; tli, Anáaski) is a state located in the Western United States on the northwest extremity of North America. A semi-exclave of the U.S. ...

; callsign KODI (closed on 20 March 1975) *Sunnyvale Control Station, callsign CUBE. Not a true tracking station, in that it had no direct downlink antenna. Instead, CUBE supported operations at TCS/Oakhangar and IOS/Seychelles, where main processing computers could not be located. CUBE had two 'sides', and so could support two satellite passes simultaneously. The

750th Space Group The United States Air Force's 750th Space Group was a space operations unit located at Onizuka Air Force Station, California. its predecessor was formed on 1 October 1987; it assumed the designation of the 750th Space Group on 30 January 1992; an ...

was inactivated in June 1999. ineage and Honors, 21st Space Operations Squadron, Air Force Historical Research Agency; Lineage and Honors, 22d Space Operations Squadron, Air Force Historical Research Agency/ref> * Colorado Tracking Station (CTS),

Schriever AFB Schriever Space Force Base, previously Schriever Air Force Base, Falcon Air Force Base, and Falcon Air Force Station, is a base of the United States Space Force located approximately east of Peterson Space Force Base near Colorado Springs in ...

; callsign PIKE. As of 2008, this site transitioned from an operational location to a testing facility, with operational support as possible. This site formally ceased operational support on 2 August 2012. It used to support various DoD satellites and previously included enhancement equipment that was used to support the Global Positioning System satellites. On 30 September 2014, the site was formally deactivated and closed. There was a tracking station on Annette Island that is one of the Alaska islands far south east of the Alaska main land area and not too far north of Seattle Washington. It was built in the mid/late 1950s and closed in the early 1960s.

References

* United States Army. (1993). Space Reference Text. US Army Space Institute: Fort Leavenworth, Kansas.

External links

Schriever AFB
{{USAF Space Command Equipment of the United States Space Force