Related Research Articles
A geostationary orbit, also referred to as a geosynchronous equatorial orbit (GEO), is a circular geosynchronous orbit 35,786 km (22,236 mi) in altitude above Earth's equator, 42,164 km (26,199 mi) in radius from Earth's center, and following the direction of Earth's rotation.
A communications satellite is an artificial satellite that relays and amplifies radio telecommunication signals via a transponder; it creates a communication channel between a source transmitter and a receiver at different locations on Earth. Communications satellites are used for television, telephone, radio, internet, and military applications. Many communications satellites are in geostationary orbit 22,236 miles (35,785 km) above the equator, so that the satellite appears stationary at the same point in the sky; therefore the satellite dish antennas of ground stations can be aimed permanently at that spot and do not have to move to track the satellite. Others form satellite constellations in low Earth orbit, where antennas on the ground have to follow the position of the satellites and switch between satellites frequently.
Skynet is a family of military communications satellites, now operated by Babcock International on behalf of the United Kingdom's Ministry of Defence (MoD). They provide strategic and tactical communication services to the branches of the British Armed Forces, the British intelligence agencies, some UK government departments and agencies, and to allied governments. Since 2015 when Skynet coverage was extended eastward, and in conjunction with an Anik G1 satellite module over America, Skynet offers near global coverage.
Orbital Sciences Corporation was an American company specializing in the design, manufacture, and launch of small- and medium- class space and launch vehicle systems for commercial, military and other government customers. In 2014, Orbital merged with Alliant Techsystems (ATK) to create a new company called Orbital ATK, which in turn was purchased by Northrop Grumman in 2018.
Milstar is a constellation of military communications satellites in geosynchronous orbit, which are operated by the United States Space Force, and provide secure and jam-resistant worldwide communications to meet the requirements of the Armed Forces of the United States. Six spacecraft were launched between 1994 and 2003, of which only five were operational after launch; the third launch failed, both damaging the satellite and leaving it in an unusable orbit.
The Mobile User Objective System (MUOS) is a United States Space Force narrowband military communications satellite system that supports a worldwide, multi-service population of users in the ultra high frequency (UHF) band. The system provides increased communications capabilities to newer, smaller terminals while still supporting interoperability with legacy terminals. MUOS is designed to support users who require greater mobility, higher bit rates and improved operational availability. The MUOS was declared fully operational for use in 2019.
The Wideband Global SATCOM system (WGS) is a high capacity United States Space Force satellite communications system planned for use in partnership by the United States Department of Defense (DoD), Canadian Department of National Defence (DND) and the Australian Department of Defence. The system is composed of the Space Segment satellites, the Terminal Segment users and the Control Segment operators.
Advanced Extremely High Frequency (AEHF) is a constellation of communications satellites operated by the United States Space Force. They are used to relay secure communications for the United States Armed Forces, the British Armed Forces, the Canadian Armed Forces, the Netherlands Armed Forces and the Australian Defence Force. The system consists of six satellites in geostationary orbits. The final satellite was launched on 26 March 2020. AEHF is backward compatible with, and replaces, the older Milstar system and will operate at 44 GHz uplink and 20 GHz downlink. The AEHF system is a joint service communications system that provides survivable, global, secure, protected, and jam-resistant communications for high-priority military ground, sea and air assets.
Galaxy 10R was an American communications satellite which was operated by PanAmSat, and later Intelsat. It was constructed by Hughes and is based on the HS-601HP satellite bus. Launch occurred on 25 January 2000, at 01:04. The launch was contracted by Arianespace, and used an Ariane 4 42L-3 carrier rocket flying from ELA-2 at the Guiana Space Centre.
Eutelsat 4A, previously Eurobird 4A and Eutelsat W1 is a French communications satellite which is operated by Eutelsat. It was constructed by Astrium is based on the Eurostar-2000+ satellite bus. Its launch was contracted by Arianespace, using an Ariane 4 44P-3 carrier rocket. The launch occurred on 6 September 2000, at 22:33 UTC from ELA-2 at the Guiana Space Centre.
TDRS-8, known before launch as TDRS-H, is an American communications satellite, of second generation, which is operated by NASA as part of the Tracking and Data Relay Satellite System. It was constructed by Boeing and is based on the BSS-601 satellite bus.
The European Data Relay System (EDRS) system is a European constellation of GEO satellites that relay information and data between satellites, spacecraft, UAVs, and ground stations. The first components were launched in 2016 and 2019.
The United States military's Air Force Satellite Communications (AFSATCOM) is a network of ground and space systems to allow rapid dissemination of communications to a worldwide audience. AFSATCOM's creation was during the height of the Cold War to guarantee that Emergency Action Messages would be received by Strategic Air Command nuclear forces.
TDRS-11, known before launch as TDRS-K, is an American communications satellite which is operated by NASA as part of the Tracking and Data Relay Satellite System. The eleventh Tracking and Data Relay Satellite is the first third-generation spacecraft.
Inmarsat-4A F4, also known as Alphasat and Inmarsat-XL, is a large geostationary communications I-4 satellite operated by United Kingdom-based Inmarsat in partnership with the European Space Agency. Launched in 2013, it is used to provide mobile communications to Africa and parts of Europe and Asia.
USA 211, or Wideband Global SATCOM 3 is a United States military communications satellite operated by the United States Air Force as part of the Wideband Global SATCOM programme. Launched in 2009, it was the third WGS satellite, and final Block I satellite, to reach orbit. It was originally stationed in geostationary orbit at 12° West.
TürkmenÄlem 52°E / MonacoSAT is a communications satellite operated by Turkmenistan National Space Agency, built by Thales Alenia Space in the Cannes Mandelieu Space Center in France. Launched from Cape Canaveral on 27 April 2015 aboard a Falcon 9 v1.1 rocket, the satellite operates at 52°E in the geostationary orbit and has an anticipated service life of 15 years. The position is controlled by the Principality of Monaco and the satellite includes 12 transponders that are referred to and commercialised as MonacoSAT as well as the 26 transponders referred to as TürkmenÄlem.
Orbital ATK Inc. was an American aerospace manufacturer and defense industry company. It was formed in February 9, 2015 from the merger of Orbital Sciences Corporation and parts of Alliant Techsystems (ATK). Orbital ATK designed, built, and delivered rocket engines, military vehicles, firearms, autocannons, missiles, ammunition, precision-guided munitions, satellites, missile approach warning systems, launch vehicles and spacecraft. The company was acquired by Northrop Grumman on June 6, 2018. The former Orbital ATK operations were renamed Northrop Grumman Innovation Systems and operated as a division until January 1, 2020 when a reorganization merged the operations into the company's other divisions.
Telstar 19V(Telstar 19 Vantage) is a communication satellite in the Telstar series of the Canadian satellite communications company Telesat. It was built by Space Systems Loral (MAXAR) and is based on the SSL-1300 bus. The satellite was designed to provide additional capacity over the North Atlantic region. As of 26 July 2018, Telstar 19V is the heaviest commercial communications satellite ever launched, weighing at 7,076 kg (15,600 lbs) and surpassing the previous record, set by TerreStar-1 (6,910 kg/15230lbs), launched by Ariane 5ECA on 1 July 2009.
While the United States Space Force gained its independence on 20 December 2019, the history of the United States Space Force can be traced back to the beginnings of the military space program following the conclusion of the Second World War in 1945. Early military space development was begun within the United States Army Air Forces by General Henry H. Arnold, who identified space as a crucial military arena decades before the first spaceflight. Gaining its independence from the Army on 18 September 1947, the United States Air Force began development of military space and ballistic missile programs, while also competing with the United States Army and United States Navy for the space mission.
References
- ↑ "Desert Storm - The First Space War". USAF Air University. Archived from the original on August 19, 1999.
- ↑ Gunter Dirk Krebs. "SLDCOM".
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