The Space Fence is a second-generation space surveillance system operated by the United States Space Force in order to track artificial satellites and space debris in Earth orbit. [1] It was constructed and designed by Lockheed Martin, Northrop Grumman, and Raytheon starting in 2009, with it being declared operational in March 2020. [1] [2] The budget is US$1.594 billion (FY15). [3] The main facility is located at Kwajalein Atoll in the Marshall Islands. [1] [4]
The initial plans to upgrade the legacy Air Force Space Surveillance System were made in 2009. The USAF 850th Electronic Systems Group, Electronic Systems Center awarded three $30-million study contracts to Lockheed Martin, Northrop Grumman, General Dynamics, and Raytheon on 11 June 2009. [5]
The new Space Fence was envisioned to be a system of two or three S-band ground-based radars designed to perform uncued detection, tracking and accurate measurement of orbiting space objects, and was intended to replace the Air Force Space Surveillance System, or VHF Fence, that was transferred from the US Navy to the US Air Force in 2004. The shorter wavelength of the S-band Space Fence will allow for the detection of much smaller satellites and debris. [5]
The 2009 satellite collision of the Iridium 33 and Kosmos 2251 communications satellites, which added hundreds more pieces of debris in orbit, highlighted the need for more precise tracking of space objects. [6]
As of 2009 [update] , data collected from the new Space Fence's sensors was planned to feed into the Joint Space Operations Center Mission System, which is used to track objects orbiting the Earth, monitor space weather, and assess foreign launches. Used by operators at the USAF 614th Air and Space Operations Center at Vandenberg Air Force Base, Calif., the 614 AOC's 24-hour-a-day, seven-day-a-week support provides vigilance of global and theater operations, and equips the Joint Functional Component Command for space operations with the tools to conduct command and control of space forces. [5]
Plans to award the final contract were delayed by the federal government's budget sequestration in early 2013 [7] and the AFSSS system was scheduled to be discontinued in October 2013 due to budget cuts. [8]
In 2014, Lockheed Martin awarded a contract for the Space Fence ground structures to General Dynamics. The ground structures include the receive array, cooling equipment, radomes and other buildings. The primary Space Fence system is located on Kwajalein Atoll in the Marshall Islands. The U. S. Space Force declared the system operational on March 28, 2020. [2]
The Space Fence will use S-band radar and will track a larger number of small objects than previous space radars: "about 200,000 objects and make 1.5 million observations per day, about 10 times the number" made by existing or recently retired US assets. [1]
Countries with space situational awareness data-sharing agreements in place with the USAF include Australia, Japan, Italy, Canada, France, South Korea, and the United Kingdom. It also "has agreements with the European Space Agency and Europe’s Eumetsat weather satellite organization." [1]
A previous system used by the USAF for the same purpose was the Air Force Space Surveillance System, which ceased operation in September 2013. [9]
The AGM-88 HARM is a tactical, air-to-surface anti-radiation missile designed to home in on electronic transmissions coming from surface-to-air radar systems. It was originally developed by Texas Instruments as a replacement for the AGM-45 Shrike and AGM-78 Standard ARM system. Production was later taken over by Raytheon Corporation when it purchased the defense production business of Texas Instruments.
The Northrop Grumman E-8 Joint Surveillance Target Attack Radar System is a retired United States Air Force (USAF) airborne ground surveillance, battle management and command and control aircraft. It tracks ground vehicles and some aircraft, collects imagery, and relays tactical pictures to ground and air theater commanders. The aircraft was operated by both active duty USAF and Air National Guard units and also carried specially trained U.S. Army personnel as additional flight crew until its retirement in 2023.
The AN/FPS-133 Air Force Space Surveillance System, colloquially known as the Space Fence, was a U.S. government multistatic radar system built to detect orbital objects passing over America. It is a component of the U.S. space surveillance network, and according to the U.S. Navy was able to detect basketball sized objects at heights up to 30,000 km (19,000 mi).
PAVE PAWS is a complex Cold War early warning radar and computer system developed in 1980 to "detect and characterize a sea-launched ballistic missile attack against the United States". The first solid-state phased array deployed used a pair of Raytheon AN/FPS-115 phased array radar sets at each site to cover an azimuth angle of 240 degrees. Two sites were deployed in 1980 at the periphery of the contiguous United States, then two more in 1987–95 as part of the United States Space Surveillance Network. One system was sold to Taiwan and is still in service.
The Defense Meteorological Satellite Program (DMSP) monitors meteorological, oceanographic, and solar-terrestrial physics for the United States Department of Defense. The program is managed by the United States Space Force with on-orbit operations provided by the National Oceanic and Atmospheric Administration (NOAA). The mission of the satellites was revealed in March 1973. They provide cloud cover imagery from polar orbits that are Sun-synchronous at nominal altitude of 830 km (520 mi).
The RCA 474L Ballistic Missile Early Warning System was a United States Air Force Cold War early warning radar, computer, and communications system, for ballistic missile detection. The network of twelve radars, which was constructed beginning in 1958 and became operational in 1961, was built to detect a mass ballistic missile attack launched on northern approaches [for] 15 to 25 minutes' warning time also provided Project Space Track satellite data.
The Northrop Grumman E-10 MC2A was planned as a multi-role military aircraft to replace the Boeing 707-based E-3 Sentry and E-8 Joint STARS, the Boeing 747-based E-4B, and the RC-135 Rivet Joint aircraft in US military service. The E-10 was based on the Boeing 767-400ER commercial airplane.
The Space-Based Infrared System (SBIRS) is a United States Space Force system intended to meet the United States' Department of Defense infrared space surveillance needs through the first two to three decades of the 21st century. The SBIRS program is designed to provide key capabilities in the areas of missile warning, missile defense, battlespace characterization and technical intelligence via satellites in geosynchronous Earth orbit (GEO), sensors hosted on satellites in highly elliptical orbit (HEO), and ground-based data processing and control.
The United States Space Surveillance Network (SSN) detects, tracks, catalogs and identifies artificial objects orbiting Earth, e.g. active/inactive satellites, spent rocket bodies, or fragmentation debris. The system is the responsibility of United States Space Command and operated by the United States Space Force and its functions are:
Cavalier Space Force Station, North Dakota, is a United States Space Force installation, where the 10th Space Warning Squadron, Space Delta 4, United States Space Force monitors and tracks potential missile launches against North America with the GE AN/FPQ-16 Enhanced Perimeter Acquisition Radar Attack Characterization System (PARCS). The PARCS also monitors and tracks over half of all earth-orbiting objects to enable space situation awareness and space control. In addition to contractors, NORAD has US and Canadian military members assigned to the facility.
The ADM-160 MALD is an air-launched, expendable decoy missile developed by the United States. Later variants (MALD-J) are additionally equipped with electronic countermeasures to actively jam early warning and target acquisition radars.
The AN/FPS-108 COBRA DANE is a PESA phased array radar installation operated by Raytheon for the United States Space Force at Eareckson Air Station on the island of Shemya, Aleutian Islands, Alaska. The system was built in 1976 and brought online in 1977 for the primary mission of gathering intelligence about Russia's ICBM program in support of verification of the SALT II arms limitation treaty. Its single face 29 m (95 ft) diameter phased array radar antenna 52.7373°N 174.0914°E faces the Kamchatka Peninsula and Russia's Kura Test Range. COBRA DANE operates in the 1215–1400 MHz band and can track items as small as a basketball sized drone at distances of several hundred miles.
The ASM-135 ASAT is an air-launched anti-satellite multistage missile that was developed by Ling-Temco-Vought's LTV Aerospace division. The ASM-135 was carried exclusively by United States Air Force (USAF) F-15 Eagle fighter aircraft.
The 1st Space Operations Squadron is a United States Space Force unit responsible for space-based space domain awareness. Located at Schriever Space Force Base, Colorado, the squadron operates the Space Based Space Surveillance system, the Advanced Technology Risk Reduction system, the Operationally Responsive Space-5 satellite, and the Geosynchronous Space Situational Awareness Program.
The Operationally Responsive Space Office is a joint initiative of the United States Department of Defense (DoD). The "stand up" of the office took place 21 May 2007 at Kirtland Air Force Base. The first director of the ORS Office was Col. Kevin McLaughlin, who was also the commander of the Space Development and Test Wing located at Kirtland. The ORS Office focuses on providing quick-response tactical space-based capabilities; utilizing smaller satellites, such as the Tactical Satellite Program and smaller launch vehicles.
The Space Tracking and Surveillance System was a pair of satellites developed by the United States Missile Defense Agency (MDA) to research the space-based detection and tracking of ballistic missiles. Data from STSS satellites could allow interceptors to engage incoming missiles earlier in flight than would be possible with other missile detection systems. The STSS program began in 2001, when the "SBIRS Low" program was transferred to MDA from the United States Air Force. In December 2002, SBIRS Low Research & Development was renamed Space Tracking and Surveillance System (STSS).
The Integrated Sensor is Structure (ISIS) was a program managed by the United States Air Force (USAF) Research Laboratory to research the feasibility of using an unmanned airship as a high-altitude aerial reconnaissance and surveillance platform. It is sometimes called Integrated Sensor is the Structure, as a fundamental innovation was the use of the airship structure as the sensing component of a state-of-the-art radar system.
Project Space Track was a research and development project of the US Air Force, to create a tracking system for all artificial satellites of the Earth and space probes, domestic and foreign.
Eglin AFB Site C-6 is a United States Space Force radar station which houses the AN/FPS-85 phased array radar, associated computer processing system(s), and radar control equipment designed and constructed for the U. S. Air Force by the Bendix Communications Division, Bendix Corporation. Commencing operations in 1969, the AN/FPS-85 was the first large phased array radar. The entire radar/computer system is located at a receiver/transmitter building and is supported by the site's power plant, fire station, 2 water wells, and other infrastructure for the system. As part of the US Space Force's Space Surveillance Network its mission is to detect and track spacecraft and other manmade objects in Earth orbit for the Combined Space Operations Center satellite catalogue. With a peak radiated power of 32 megawatts the Space Force claims it is the most powerful radar in the world, and can track a basketball-sized object up to 22,000 nautical miles (41,000 km) from Earth.
Beam park is a radar mode used for space surveillance, particularly tracking space debris. In beam-park mode, a radar beam is kept in a fixed direction with respect to the Earth, while objects passing through the beam are tracked. In 24 hours, as a result of the Earth’s rotation, the radar effectively scans a narrow strip through 360° of the celestial sphere. The scattered waves are detected by a receiver and the measurements obtained during the observations can be used to determine object radar cross-section, time of peak occurrence, polarization ratio, doppler shift and object rotation. The obtained information for each object is then processed and matched against data from previously catalogued objects. The beam-park mode can be used to detect both previously known and uncatalogued objects at any altitude, provided that the reflected power captured by the receiver can be distinguished from the noise. This limits the use of radar-based beam park observations to objects in Low-Earth Orbit (LEO). Optical instruments, in turn, have very good performance for objects in Geostationary Earth Orbit (GEO) and in Geostationary Transfer Orbit (GTO). The radar technique typically outperforms optical facilities in LEO and can conduct observations for longer periods, both during day and night, independently of the weather and object illumination by sunlight.
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