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A military satellite is an artificial satellite used for a military purpose. The most common missions are intelligence gathering, navigation and military communications.
The first military satellites were photographic reconnaissance missions. Some attempts were made to develop satellite based weapons but this work was halted in 1967 following the ratification of international treaties banning the deployment of weapons of mass destruction in orbit.
As of 2013, there are 950 satellites of all types in Earth orbit. It is not possible to identify the exact number of these that are military satellites partly due to secrecy and partly due to dual purpose missions such as GPS satellites that serve both civilian and military purposes. As of December 2018 there are 320 known military or dual-use satellites in the sky, half of which are owned by the US, followed by Russia, China and India. [1]
The first military use of satellites was for reconnaissance.
In the United States the first formal military satellite programs, Weapon System 117L, was developed in the mid-1950s. [2] Within this program a number of sub-programs were developed including Corona. [2] Satellites within the Corona program carried different code names. The first launches were code named Discoverer. This mission was a series of reconnaissance satellites, designed to enter orbit, take high-resolution photographs and then return the payload to Earth via parachute. [2] Discoverer 1, the first mission, was launched on 28 February 1959 although it didn't carry a payload being intended as a test flight to prove the technology. [3] Corona was followed by other programs including Canyon (seven launches between 1968 and 1977 [4] ), Aquacade [5] and Orion (stated by US Government sources to be extremely large [6] ). There have also been a number of subsequent programs including Magnum and Trumpet, [7] but these remain classified and therefore many details remain speculative.
The Soviet Union began the Almaz (Russian : Алмаз) program in the early 1960s. This program involved placing space stations in Earth orbit as an alternative to satellites. Three stations were launched between 1973 and 1976: Salyut 2, Salyut 3 and Salyut 5. Following Salyut 5, the Soviet Ministry of Defence judged in 1978 that the time consumed by station maintenance outweighed the benefits relative to automatic reconnaissance satellites.[ citation needed ]
In 2015, United States military space units and commercial satellite operator Intelsat became concerned about apparent reconnaissance test maneuvers by the Russian satellite Olymp-K, launched in September 2014, when it maneuvered between Intelsat 7 and Intelsat 901, which are located only half a degree from one another in geosynchronous orbit. [8]
The first satellite navigation system, Transit, used by the United States Navy, was tested in 1960. [9] It used a constellation of five satellites and could provide a navigational fix approximately once per hour.
During the Cold War arms race, the nuclear threat was used to justify the cost of providing a more capable system. These developments led eventually to the deployment of the Global Positioning System (GPS). The US Navy required precise navigation to enable submarines to get an accurate fix of their positions before they launched their SLBMs. [10] The USAF had requirements for a more accurate and reliable navigation system, as did the United States Army for geodetic surveying [11] for which purpose they had developed the SECOR system. SECOR used ground-based transmitters from known locations that sent signals to satellite transponder in orbit. A fourth ground-based station, at an undetermined position, could then use those signals to fix its location precisely. The last SECOR satellite was launched in 1969. [12]
In 1978, the first experimental Block-I GPS satellite was launched [13] and by December 1993, GPS achieved initial operational capability (IOC), indicating a full constellation (24 satellites) was available and providing the Standard Positioning Service (SPS). [14] Full Operational Capability (FOC) was declared by Air Force Space Command (AFSPC) in April 1995, signifying full availability of the military's secure Precise Positioning Service (PPS). [14]
A number of nations have developed satellite based early warning systems designed to detect ICBMs during different flight phases. In the United States these satellites are operated by the Defense Support Program (DSP). The first launch of a DSP satellite was on 6 November 1970 with the 23rd and last launched 10 November 2007. This program has been superseded by the Space-Based Infrared System (SBIRS).
In the United States, research into satellite based weapons was initiated by President Dwight D. Eisenhower in the 1950s. In 1958, the United States initiated Project Defender to develop an anti-ICBM solution launched from satellites. The satellites would have deployed a huge wire mesh to disable ICBMs during their early launch phase. The project floundered due to the lack of any mechanism to protect the satellites from attack resulting in the cancellation of Defender in 1968. [15]
Since October 1967 satellite based weapons systems have been limited by international treaty to conventional weapons only. Art.IV of the Outer Space Treaty specifically prohibits signatories from installing weapons of mass destruction in Earth orbit. The treaty became effective on 10 October 1967 and, as of May 2013, 102 countries are parties to the treaty with a further 27 pending full ratification. [16] [17]
Communications satellites are used for military communications applications. Typically military satellites operate in the UHF, SHF (also known as X-band) or EHF (also known as Ka band) frequency bands.
The US Armed Forces maintains international networks of satellites with ground stations located in various continents. Signal latency is a major concern in satellite communications, so geographic and meteorological factors play an important role in choosing teleports. Since some of the major military activities of the U.S. army are in foreign territories, the U.S. government needs to subcontract satellite services to foreign carriers headquartered in areas with favorable climate. [18]
Military Strategic and Tactical Relay, or Milstar, is a constellation of military satellites managed by the United States Space Force. Six spacecraft were launched between 1994 and 2003, of which five are operational, with the sixth lost in a launch failure. They are deployed in geostationary orbit and provide wideband, narrowband and protected military communication systems. Wideband systems support high-bandwidth transfers. Protected systems offer more sophisticated security protection like antijam features and nuclear survivability, while narrowband systems are intended for basic communications services that do not require high bandwidth.
The United Kingdom also operates military communication satellites through its Skynet system. This is currently operated with support from Astrium Services and provides near worldwide coverage with both X band and Ultra high frequency services. [19]
Skynet 5 is the United Kingdom's most recent military communications satellite system. There are four Skynet satellites in orbit, with the latest launch completed in December 2012. [20] The system is provided by a private contractor, Astrium, with the UK government paying service charges based on bandwidth consumption. [20]
Rank | Country | Military satellites | Ref. |
---|---|---|---|
1 | United States | 247 | [21] [22] |
2 | China | 157 | [21] [22] |
3 | Russia | 110 | [21] [22] |
4 | France | 17 | [21] [22] |
5 | Israel | 12 | [21] [22] |
6 | Italy | 10 | [21] [22] |
7 | India | 9 | [21] [22] |
8 | Germany | 8 | [21] [22] |
9 | United Kingdom | 6 | [21] [22] |
10 | Spain | 4 | [21] [22] |
11 | Turkey | 3 | [23] |
12 | Iran | 2 | [21] [22] |
The Global Positioning System (GPS), originally Navstar GPS, is a satellite-based radio navigation system owned by the United States Space Force and operated by Mission Delta 31. It is one of the global navigation satellite systems (GNSS) that provide geolocation and time information to a GPS receiver anywhere on or near the Earth where there is an unobstructed line of sight to four or more GPS satellites. It does not require the user to transmit any data, and operates independently of any telephone or Internet reception, though these technologies can enhance the usefulness of the GPS positioning information. It provides critical positioning capabilities to military, civil, and commercial users around the world. Although the United States government created, controls, and maintains the GPS system, it is freely accessible to anyone with a GPS receiver.
An intercontinental ballistic missile (ICBM) is a ballistic missile with a range greater than 5,500 kilometres (3,400 mi), primarily designed for nuclear weapons delivery. Conventional, chemical, and biological weapons can also be delivered with varying effectiveness, but have never been deployed on ICBMs. Most modern designs support multiple independently targetable reentry vehicle (MIRVs), allowing a single missile to carry several warheads, each of which can strike a different target. The United States, Russia, China, France, India, the United Kingdom, Israel, and North Korea are the only countries known to have operational ICBMs. Pakistan is the only nuclear-armed state that does not possess ICBMs.
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.
Anti-satellite weapons (ASAT) are space weapons designed to incapacitate or destroy satellites for strategic or tactical purposes. Although no ASAT system has yet been utilized in warfare, a few countries have successfully shot down their own satellites to demonstrate their ASAT capabilities in a show of force. ASATs have also been used to remove decommissioned satellites.
Space warfare is combat in which one or more belligerents are in outer space. The scope of space warfare includes ground-to-space warfare, such as attacking satellites from the Earth; space-to-space warfare, such as satellites attacking satellites; and space-to-ground warfare, such as satellites attacking Earth-based targets. Space warfare in fiction is thus sub-genre and theme of science fiction, where it is portrayed with a range of realism and plausibility. In the real world, international treaties are in place that attempt to regulate conflicts in space and limit the installation of space weapon systems, especially nuclear weapons.
Lockheed Martin Space is one of the four major business divisions of Lockheed Martin. It has its headquarters in Littleton, Colorado, with additional sites in Valley Forge, Pennsylvania; Sunnyvale, California; Santa Cruz, California; Huntsville, Alabama; and elsewhere in the United States and United Kingdom. The division currently employs about 20,000 people, and its most notable products are commercial and military satellites, space probes, missile defense systems, NASA's Orion spacecraft, and the Space Shuttle external tank.
Space weapons are weapons used in space warfare. They include weapons that can attack space systems in orbit, attack targets on the earth from space or disable missiles travelling through space. In the course of the militarisation of space, such weapons were developed mainly by the contesting superpowers during the Cold War, and some remain under development today. Space weapons are also a central theme in military science fiction and sci-fi video games.
The militarisation of space involves the placement and development of weaponry and military technology in outer space. The early exploration of space in the mid-20th century had, in part, a military motivation, as the United States and the Soviet Union used it as an opportunity to demonstrate ballistic-missile technology and other technologies having the potential for military application. Outer space has since been used as an operating location for military spacecraft such as imaging and communications satellites, and some ballistic missiles pass through outer space during their flight. As of 2018, known deployments of weapons stationed in space include only the Almaz space-station armament and pistols such as the TP-82 Cosmonaut survival pistol.
The Aerospace Corporation is an American nonprofit corporation that operates a federally funded research and development center (FFRDC) in El Segundo, California. The corporation provides technical guidance and advice on all aspects of space missions to military, civil, and commercial customers. As the FFRDC for national-security space, Aerospace works closely with organizations such as the United States Space Force (USSF) and the National Reconnaissance Office (NRO) to provide "objective technical analyses and assessments for space programs that serve the national interest". Although the USSF and NRO are the primary customers, Aerospace also performs work for civil agencies such as NASA and NOAA as well as international organizations and governments in the national interest.
Nuclear weapons delivery is the technology and systems used to place a nuclear weapon at the position of detonation, on or near its target. Several methods have been developed to carry out this task.
The British space programme is the British government's work to develop British space capabilities. The objectives of the current civil programme are to "win sustainable economic growth, secure new scientific knowledge and provide benefits to all citizens."
Astrium was a European aerospace company and subsidiary of the European Aeronautic Defence and Space Company (EADS), headquartered in Paris. It designed, developed and manufactured civil and military space systems and provided related services from 2006 to 2013. In 2012, Astrium had a turnover of €5.8 billion and 18,000 employees in France, Germany, the United Kingdom, Spain and the Netherlands. Astrium was a member of Institute of Space, its Applications and Technologies.
Space Systems Command (SSC) is the United States Space Force's space development, acquisition, launch, and logistics field command. It is headquartered at Los Angeles Air Force Base, California, and manages the United States' space launch ranges.
Space policy is the political decision-making process for, and application of, public policy of a state regarding spaceflight and uses of outer space, both for civilian and military purposes. International treaties, such as the 1967 Outer Space Treaty, attempt to maximize the peaceful uses of space and restrict the militarization of space.
USA-213, also known as GPS SVN-62, GPS IIF SV-1 and NAVSTAR 65, is the first satellite in the Block IIF series of Global Positioning System navigation satellites. It will be used to relay signals for the United States Air Force Navstar Global Positioning System (GPS). The satellite was launched at 03:00:00 UTC on 28 May 2010. It will be placed into plane B of the GPS constellation, and will transmit the PRN-25 signal. PRN-25 was previously broadcast by USA-79, which was retired in late 2009 after almost eighteen years of service.
A hosted payload is a module attached to a commercial satellite with communications circuitry that operates independently of the main spacecraft but which shares the satellite's power supply and transponders. The concept has been also been referred to as "piggybacking" or "hitchhiking."
USA-79, also known as GPS IIA-3, GPS II-12 and GPS SVN-25, was an American navigation satellite which formed part of the Global Positioning System. It was the third of nineteen Block IIA GPS satellites to be launched.
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.