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Satellite Data System
The Satellite Data System (SDS) is a system of United States military communications satellites. At least three generations have been used: SDS-1 from 1976 to 1987; SDS-2 from 1989 to 1996; SDS-3 from 1998 to the present. It is believed that these satellites were known by the code name ''Quasar''. The first generation was named simply 'SDS', the second generation was named 'Quasar' and the third generation each had their own designations. Orbital characteristics SDS satellites have a highly elliptical orbit, going from about 300 kilometers at perigee to roughly 39,000 km at apogee in order to allow communications with polar stations that cannot contact geosynchronous satellites. The high apogee meant that the polar regions were visible for long amounts of time, and only two satellites were required in order to achieve constant communications ability. In addition, two geostationary satellites appear to be part of the system. The SDS satellites were constructed by Hughe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photovoltaic Module
Photovoltaics (PV) is the conversion of light into electricity using semiconducting materials that exhibit the photovoltaic effect, a phenomenon studied in physics, photochemistry, and electrochemistry. The photovoltaic effect is commercially used for electricity generation and as photosensors. A photovoltaic system employs solar modules, each comprising a number of solar cells, which generate electrical power. PV installations may be ground-mounted, rooftop-mounted, wall-mounted or floating. The mount may be fixed or use a solar tracker to follow the sun across the sky. Photovoltaic technology helps to mitigate climate change because it emits much less carbon dioxide than fossil fuels. Solar PV has specific advantages as an energy source: once installed, its operation generates no pollution and no greenhouse gas emissions, it shows scalability in respect of power needs and silicon has large availability in the Earth's crust, although other materials required in PV syste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Designator
The International Designator, also known as COSPAR ID, is an international identifier assigned to artificial objects in space. It consists of the launch year, a three-digit incrementing launch number of that year and up to a three-letter code representing the sequential identifier of a piece in a launch. In TLE format the first two digits of the year and the dash are dropped. For example1990-037Ais the Space Shuttle ''Discovery'' on mission STS-31, which carried the Hubble Space Telescope1990-037B into space. This launch was the 37th known successful launch worldwide in 1990. The designation system has been generally known as the COSPAR system, named for the Committee on Space Research (COSPAR) of the International Council for Science. COSPAR subsumed the first designation system, devised at Harvard University. That system used letters of the Greek alphabet to designate artificial satellites. This was based on the scientific naming convention for natural satellites. For exampl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Launch Vehicle
A launch vehicle or carrier rocket is a rocket designed to carry a payload ( spacecraft or satellites) from the Earth's surface to outer space. Most launch vehicles operate from a launch pads, supported by a launch control center and systems such as vehicle assembly and fueling. Launch vehicles are engineered with advanced aerodynamics and technologies, which contribute to large operating costs. An orbital launch vehicle must lift its payload at least to the boundary of space, approximately and accelerate it to a horizontal velocity of at least . Suborbital vehicles launch their payloads to lower velocity or are launched at elevation angles greater than horizontal. Practical orbital launch vehicles are multistage rockets which use chemical propellants such as solid fuel, liquid hydrogen, kerosene, liquid oxygen, or Hypergolic propellants. Launch vehicles are classified by their orbital payload capacity, ranging from small-, medium-, heavy- to super-heavy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Titan IV
Titan IV was a family of heavy-lift space launch vehicles developed by Martin Marietta and operated by the United States Air Force from 1989 to 2005. Launches were conducted from Cape Canaveral Air Force Station, Florida and Vandenberg Air Force Base, California. The Titan IV was the last of the Titan family of rockets, originally developed by the Glenn L. Martin Company in 1958. It was retired in 2005 due to their high cost of operation and concerns over its toxic hypergolic propellants, and replaced with the Atlas V and Delta IV launch vehicles under the EELV program. The final launch (B-30) from Cape Canaveral occurred on 29 April 2005, and the final launch from Vandenberg AFB occurred on 19 October 2005. Lockheed Martin Space Systems built the Titan IVs near Denver, Colorado, under contract to the US government. Two Titan IV vehicles are currently on display at the National Museum of the United States Air Force in Dayton, Ohio and the Evergreen Aviation and Space Muse ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
STS-53
STS-53 was a NASA Space Shuttle ''Discovery'' mission in support of the United States Department of Defense (DoD). The mission was launched on December 2, 1992, from Kennedy Space Center, Florida. Crew Mission highlights ''Discovery'' carried a classified primary payload (DOD-1) for the United States Department of Defense (DoD), two unclassified secondary payloads and nine unclassified middeck experiments. ''Discovery''s primary payload, USA-89 (1992-086B) is also known a"DoD-1" and was the shuttle's last major payload for the Department of Defense. The satellite was the third launch of a Satellite Data System-2 (SDS 2-3) military communications satellite, after USA-40 on STS-28 and STS-38's deployment of USA-67. Secondary payloads contained in or attached to Get Away Special (GAS) hardware in the cargo bay included the Orbital Debris Radar Calibration Spheres ( ODERACS) satellites and the combined Shuttle Glow Experiment/Cryogenic Heat Pipe Experiment (GCP). M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
STS-38
STS-38 was a Space Shuttle mission by NASA using the Space Shuttle ''Atlantis''. It was the 37th shuttle mission, and carried a classified payload for the U.S. Department of Defense (DoD). It was the seventh flight for ''Atlantis'' and the seventh flight dedicated to the Department of Defense. The mission was a 4-day mission that traveled and completed 79 revolutions. ''Atlantis'' landed at Kennedy Space Center's Shuttle Landing Facility's runway 33. The launch was originally scheduled for July 1990, but was rescheduled due to a hydrogen leak found on during the STS-35 countdown. During a rollback to the Orbiter Processing Facility ''Atlantis'' was damaged during a hail storm. The eventual launch date of November 15, 1990, was set due to a payload problem. The launch window was between 18:30 and 22:30 EST. The launch occurred at 18:48:13 EST. Crew Crew seating arrangements Preparations and launch The launch occurred on November 15, 1990, 18:48:13 EST. It was or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
STS-28
STS-28 was the 30th NASA Space Shuttle mission, the fourth shuttle mission dedicated to United States Department of Defense (DoD) purposes, and the eighth flight of Space Shuttle ''Columbia''. The mission launched on August 8, 1989, and traveled during 81 orbits of the Earth, before landing on runway 17 of Edwards Air Force Base, California, on August 13, 1989. STS-28 was also ''Columbia''s first flight since January 1986, when it had flown STS-61-C, the mission directly preceding the ''Challenger'' disaster of STS-51-L. The mission details of STS-28 are classified, but the payload is widely believed to have been the first SDS-2 relay communications satellite. The altitude of the mission was between and . The mission was officially designated STS-28R as the original STS-28 designator belonged to STS-51-J, the 21st Space Shuttle mission. Official documentation for that mission contained the designator STS-28 throughout. As STS-51-L was designated STS-33, future flights w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Space Shuttle Program
The Space Shuttle program was the fourth human spaceflight program carried out by the U.S. National Aeronautics and Space Administration (NASA), which accomplished routine transportation for Earth-to-orbit crew and cargo from 1981 to 2011. Its official name, Space Transportation System (STS), was taken from a 1969 plan for a system of reusable spacecraft of which it was the only item funded for development. It flew 135 missions and carried 355 astronauts from 16 countries, many on multiple trips. The Space Shuttle—composed of an orbiter launched with two reusable solid rocket boosters and a disposable external fuel tank—carried up to eight astronauts and up to of payload into low Earth orbit (LEO). When its mission was complete, the orbiter would reenter the Earth's atmosphere and land like a glider at either the Kennedy Space Center or Edwards Air Force Base. The Shuttle is the only winged crewed spacecraft to have achieved orbit and landing, and the first re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
K Band (IEEE)
The IEEE K-band is a portion of the radio spectrum in the microwave range of frequencies from 18 to 27-Gigahertz (GHz). The range of frequencies in the center of the K-band between 18- and 26.5-GHz is absorbed by water vapor in the atmosphere due to its resonance peak at 22.24-GHz, . Therefore these frequencies experience high atmospheric attenuation and cannot be used for long distance applications. For this reason the original K-band has been split into three bands, Ka-band, K-band, and Ku-band as detailed below. The K stands for Kurz which stems from the German word for short. Subdivisions Because of the water vapor absorption peak in the center of the band, the IEEE K-band is conventionally divided into three sub-bands: * Ku-band: K-under band, 12–18-GHz, mainly used for satellite communications, direct-broadcast satellite television, terrestrial microwave communications, and radar, especially police traffic-speed detectors. * K-band 18–27-GHz: Due to the 22-GHz wate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
KH-11 Kennen
The KH-11 KENNEN (later renamed CRYSTAL,p.199-200 then Evolved Enhanced CRYSTAL System, and codenamed 1010 and Key Hole) is a type of reconnaissance satellite first launched by the American National Reconnaissance Office (NRO) in December 1976. Manufactured by Lockheed in Sunnyvale, California, the KH-11 was the first American spy satellite to use electro-optical digital imaging, and so offer real-time optical observations. Later KH-11 satellites have been referred to by outside observers as KH-11B or KH-12, and by the names "Advanced KENNEN", "Improved Crystal" and "Ikon". Official budget documents refer to the latest generation of electro-optical satellites as ''Evolved Enhanced CRYSTAL System''. The Key Hole series was officially discontinued in favor of a random numbering scheme after repeated public references to KH-7 GAMBIT, KH-8 GAMBIT 3, KH-9 HEXAGON, and KH-11 KENNEN satellites. The capabilities of the KH-11 are highly classified, as are images they produce. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Signals Intelligence
Signals intelligence (SIGINT) is intelligence-gathering by interception of '' signals'', whether communications between people (communications intelligence—abbreviated to COMINT) or from electronic signals not directly used in communication (electronic intelligence—abbreviated to ELINT). Signals intelligence is a subset of intelligence collection management. As classified and sensitive information is usually encrypted, signals intelligence in turn involves the use of cryptanalysis to decipher the messages. Traffic analysis—the study of who is signaling whom and in what quantity—is also used to integrate information again. History Origins Electronic interceptions appeared as early as 1900, during the Boer War of 1899–1902. The British Royal Navy had installed wireless sets produced by Marconi on board their ships in the late 1890s, and the British Army used some limited wireless signalling. The Boers captured some wireless sets and used them to make vital tran ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
