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DSCS
The Defense Satellite Communications System (DSCS) is a United States Space Force satellite constellation that provides the United States with military communications to support globally distributed military users. Beginning in 2007, DSCS began being replaced by the Wideband Global SATCOM system. A total of 14 DSCS-III satellites were launched between the early 1980s and 2003. Two satellites were launched aboard the Space Shuttle ''Atlantis'' in 1985 during the STS-51-J flight. As of 14 September 2021, six DSCS-III satellites were still operational. DSCS operations are currently run by the 4th Space Operations Squadron out of Schriever Space Force Base. Background DSCS went through three major phases — IDCSP (Interim Defense Communication Satellite Program), DSCS-II, and DSCS-III. Since the first launch, DSCS has been the "workhorse" of military satellite communications. All DSCS III satellites have exceeded their 10-year design life. The National Science Foundation use ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wideband Global SATCOM
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. DoD wideband satellite communication services are currently provided by a combination of the existing Defense Satellite Communications System (DSCS) and Global Broadcast Service (GBS) satellites. According to United Launch Alliance, quoted on ''Spaceflight Now'', "A single WGS spacecraft has as much bandwidth as the entire existing DSCS constellation." WGS operations are currently run by the 4th Space Operations Squadron, out of Schriever Space Force Base, as well as the 53rd Space Operations Squadron. Mission The constellation of WGS satellites increases the commun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
STS-51-J
STS-51-J was NASA's 21st Space Shuttle mission and the maiden flight of Space Shuttle ''Atlantis''. It launched from Kennedy Space Center, Florida, on October 3, 1985, carrying a payload for the U.S. Department of Defense (DoD), and landed at Edwards Air Force Base, California, on October 7, 1985. Crew Backup crew Crew seat assignments Mission summary STS-51-J launched on October 3, 1985, at 15:15:30 UTC (11:15:30 a.m. EDT), from Launch Pad 39A at the Kennedy Space Center. The launch was delayed by 22 minutes and 30 seconds due to a problem with a main engine liquid hydrogen prevalve close remote power controller; the controller was showing a faulty "on" indication. The mission was the second shuttle flight totally dedicated to deploying a United States Department of Defense payload, after STS-51-C. Its cargo was classified, but it was reported that twoUSA-11anUSA-12 DSCS-III (Defense Satellite Communications System) satellites were launched into geostati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Initial Defense Communications Satellite Program
The Initial Defense Communications Satellite Program or IDCSP was the first United States Department of Defense communications satellite constellation and the first stage of the Defense Communications Satellite Program (DCSP). Launched in five groups by Titan IIIC launch vehicles to near equatorial, subsynchronous orbits between 1966 and 1968, they were intended to be experimental testbeds. They were so successful that, by the time of the launch of the last set of eight satellites, the IDCSP was deemed operational and renamed Initial Defense Satellite Communications System or IDSCS. This system allowed real-time collection of battlefield intelligence during the Vietnam War. A total of 35 IDCSP satellites were launched, 27 successfully. Background The Initial Defense Communications Satellite Program or IDCSP was the first stage in the Defense Communications Satellite Program (DCSP) commissioned by United States Secretary of Defense Robert McNamara in 1962. Under the DCSP, se ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amundsen–Scott South Pole Station
The Amundsen–Scott South Pole Station is a science and technology in the United States, United States scientific research station at the South Pole of the Earth. It is the List of extreme points of the United States, southernmost point under the jurisdiction (not sovereignty) of the United States. The station is located on the high Antarctic Plateau, plateau of Antarctica at above sea level. It is administered by the Office of Polar Programs of the National Science Foundation, specifically the United States Antarctic Program (USAP). It is named in honor of Norwegian Roald Amundsen and Briton Robert Falcon Scott, Robert F. Scott, leaders of the competing first and second expeditions to reach the pole, in the summer of 1911–1912. The original Amundsen–Scott Station was built by Seabee, Navy Seabees for the federal government of the United States during November 1956, as part of its commitment to the Science, scientific goals of the International Geophysical Year, an ef ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Space Force
The United States Space Force (USSF) is the space force branch of the United States Department of Defense. It is one of the six United States Armed Forces, armed forces of the United States and one of the eight uniformed services of the United States. It is also one of two List of space forces, units, and formations#Independent space forces, independent space forces in the world. The United States Space Force traces its origins to the Air Force, Army, and Navy's military space programs created during the beginning of the Cold War. US military space forces first participated in combat operations during the Vietnam War and have participated in every U.S. military operation since, most notably in the Gulf War, which has been referred to as the "first space war." The Strategic Defense Initiative and creation of Air Force Space Command in the 1980s marked a renaissance for military space operations. Proposals for a U.S. Space Force were first seriously considered during the Reagan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Communications Satellite
A communications satellite is an artificial satellite that relays and amplifies radio telecommunication signals via a Transponder (satellite communications), transponder; it creates a communication channel between a source transmitter and a Radio receiver, 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 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. The radio waves used for telecommunications links travel by Line-of-sight propagation, line of sight and so are obstructe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Space Shuttle Atlantis
Space Shuttle ''Atlantis'' (Orbiter Vehicle designation: OV‑104) is a retired Space Shuttle orbiter vehicle which belongs to NASA, the spaceflight and space exploration agency of the United States. ''Atlantis'' was manufactured by the Rockwell International company in Southern California and was delivered to the Kennedy Space Center in Eastern Florida in April 1985. ''Atlantis'' is the fourth operational and the second-to-last Space Shuttle built. Its maiden flight was STS-51-J made from October 3 to 7, 1985. ''Atlantis'' embarked on its 33rd and final mission, also the final mission of a space shuttle, STS-135, on July 8, 2011. STS-134 by Space Shuttle Endeavour, ''Endeavour'' was expected to be the final flight before STS-135 was authorized in October 2010. STS-135 took advantage of the processing for the STS-335 Launch on Need mission that would have been necessary if STS-134's crew became stranded in orbit. ''Atlantis'' landed for the final time at the Kennedy Space Cent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Defense Information Systems Agency
The Defense Information Systems Agency (DISA), known as the Defense Communications Agency (DCA) until 1991, is a United States Department of Defense (DoD) combat support agency. It is composed of military, federal civilians, and contractors. DISA provides information technology (IT) and communications support to the President, Vice President, Secretary of Defense, the Department of Defense, the combatant commands, and any individual or system contributing to the defense of the United States. History 1960s: The Defense Communications Agency DCA was established May 12, 1960, with the primary mission of operational control and management of the Defense Communications System (DCS). The initial headquarters for 34 DCA members was Wake Hall, one of a complex of three buildings (which included Midway Hall and Guam Hall) on the site where the parking lot of the Robert F. Kennedy Stadium in Washington, D.C., stands today. Navy Rear Admiral William D. Irvin became the first DCA ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Research And Development
Research and development (R&D or R+D), known in some countries as OKB, experiment and design, is the set of innovative activities undertaken by corporations or governments in developing new services or products. R&D constitutes the first stage of development of a potential new service or the production process. Although R&D activities may differ across businesses, the primary goal of an R&D department is to new product development, develop new products and services. R&D differs from the vast majority of corporate activities in that it is not intended to yield immediate profit, and generally carries greater risk and an uncertain return on investment. R&D is crucial for acquiring larger shares of the market through new products. ''R&D&I'' represents R&D with innovation. Background New product design and development is often a crucial factor in the survival of a company. In a global industrial landscape that is changing fast, firms must continually revise their design and range of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antenna (radio)
In radio-frequency engineering, an antenna (American English) or aerial (British English) is an electronic device that converts an alternating current, alternating electric current into radio waves (transmitting), or radio waves into an electric current (receiving). It is the interface between radio waves Radio propagation, propagating through space and electric currents moving in metal Electrical conductor, conductors, used with a transmitter or receiver (radio), receiver. In transmission (telecommunications), transmission, a radio transmitter supplies an electric current to the antenna's Terminal (electronics), terminals, and the antenna radiates the energy from the current as electromagnetic radiation, electromagnetic waves (radio waves). In receiver (radio), reception, an antenna intercepts some of the power of a radio wave in order to produce an electric current at its terminals, that is applied to a receiver to be amplifier, amplified. Antennas are essential components ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transponder
In telecommunications, a transponder is a device that, upon receiving a signal, emits a different signal in response. The term is a blend of ''transmitter'' and ''responder''. In air navigation or radio frequency identification, a flight transponder is an automated transceiver in an aircraft that emits a coded identifying signal in response to an interrogating received signal. In a communications satellite, a satellite transponder receives signals over a range of uplink frequencies, usually from a satellite ground station; the transponder amplifies them, and re-transmits them on a different set of downlink frequencies to receivers on Earth, often without changing the content of the received signal or signals. Satellite/broadcast communications A communications satellite’s channels are called transponders because each is a separate transceiver or repeater. With digital video data compression and multiplexing, several video and audio channels may travel through a single tr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Armed Forces
The United States Armed Forces are the Military, military forces of the United States. U.S. United States Code, federal law names six armed forces: the United States Army, Army, United States Marine Corps, Marine Corps, United States Navy, Navy, United States Air Force, Air Force, United States Space Force, Space Force, and the United States Coast Guard, Coast Guard. Since 1949, all of the armed forces, except the Coast Guard, have been permanently part of the United States Department of Defense. They form six of the eight uniformed services of the United States. Each of the different military services is assigned a role and domain. The Army conducts land operations. The Navy and Marine Corps conduct maritime operations, the Marine Corps specializing in amphibious and maritime littoral operations primarily for supporting the Navy. The Air Force conducts air operations. The Space Force conducts space operations. The Coast Guard is unique in that it specializes in maritime opera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
