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SBS 2 (satellite)
SBS 2 was a geostationary communications satellite designed and manufactured by Hughes (now Boeing) on the HS-376 platform. It was ordered by Satellite Business Systems, which later sold it to Hughes Communications. It had a Ku band payload and operated on the 117°W longitude. Satellite description The spacecraft was designed and manufactured by Hughes on the HS-376 satellite bus. It had a launch mass of , a geostationary orbit and a 7-year design life. History On September 24, 1981, SDS 2 was finally launched by a Delta-3910 PAM-D from Cape Canaveral at 23:09 UTC. In April 1996, SDS 2 finally decommissioned and put on a graveyard orbit. References See also * 1981 in spaceflight The following is an outline of 1981 in spaceflight. Launches , colspan="8", January , - , colspan="8", February , - , colspan="8", March , - , co ... Communications satellites ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Communications
Communication (from la, communicare, meaning "to share" or "to be in relation with") is usually defined as the transmission of information. The term may also refer to the message communicated through such transmissions or the field of inquiry studying them. There are many disagreements about its precise definition. John Peters argues that the difficulty of defining communication emerges from the fact that communication is both a universal phenomenon and a specific discipline of institutional academic study. One definitional strategy involves limiting what can be included in the category of communication (for example, requiring a "conscious intent" to persuade). By this logic, one possible definition of communication is the act of developing meaning among entities or groups through the use of sufficiently mutually understood signs, symbols, and semiotic conventions. An important distinction is between verbal communication, which happens through the use of a language, and ... [...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; 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 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 high frequency radio waves used for telecommunications links travel by line of sight and so are obstructed by the curve of the Earth. The purpose of communications sate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1981 In Spaceflight
The following is an outline of 1981 in spaceflight. Launches , colspan="8", January , - , colspan="8", February , - , colspan="8", March , - , colspan="8", April , - , colspan="8", May , - , colspan="8", June , - , colspan="8", July , - , colspan="8", August , - , colspan="8", September , - , colspan="8", October , - , colspan="8", November , - , colspan="8", December , - Deep-space rendezvous References Footnotes {{Orbital launches in 1981 Spaceflight by year ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Graveyard Orbit
A graveyard orbit, also called a junk orbit or disposal orbit, is an orbit that lies away from common operational orbits. One significant graveyard orbit is a supersynchronous orbit well beyond geosynchronous orbit. Some satellites are moved into such orbits at the end of their operational life to reduce the probability of colliding with operational spacecraft and generating space debris. Overview A graveyard orbit is used when the change in velocity required to perform a de-orbit maneuver is too large. De-orbiting a geostationary satellite requires a delta-v of about , whereas re-orbiting it to a graveyard orbit only requires about . For satellites in geostationary orbit and geosynchronous orbits, the graveyard orbit is a few hundred kilometers beyond the operational orbit. The transfer to a graveyard orbit beyond geostationary orbit requires the same amount of fuel as a satellite needs for about three months of stationkeeping. It also requires a reliable attitude control d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Satellite Bus
A satellite bus (or spacecraft bus) is the main body and structural component of a satellite or spacecraft, in which the payload and all scientific instruments are held. Bus-derived satellites are opposed to specially produced satellites. Bus-derived satellites are usually customized to customer requirements, for example with specialized sensors or transponders, in order to achieve a specific mission. They are commonly used for geosynchronous satellites, particularly communications satellites, but are also used in spacecraft which occupy lower orbits, occasionally including low Earth orbit missions. Examples Some satellite bus examples include: * Boeing DS&S 702 * Lockheed Martin Space Systems A2100 * Alphabus * INVAP ARSAT-3K * Airbus D&S Eurostar * ISRO's I-1K, I-2K, I-3K, I-4K, I-6K, and Indian Mini Satellite bus * NASA Ames MCSB * SSL 1300 * Orbital ATK GEOStar * Mitsubishi Electric DS2000 * Spacecraft bus of the James Webb Space Telescope * SPUTNIX TabletSat * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hughes Communications
Hughes Network Systems, LLC is a wholly owned subsidiary of EchoStar. It is headquartered in Germantown, Maryland and provides satellite internet service. HughesNet has over 1.3 million subscribers in the Americas. History Hughes Communications was founded in 1971 under the name Digital Communication Corporation (DCC) by a group of seven engineers and a lawyer led by John Puente and Dr. Burton Edelson, who all previously worked together at Comsat Laboratories. With $40,000 in startup capital, the company operated from a garage in Rockville, Maryland, designing circuit boards for telecom related products. By 1977, Digital Communications Corp. had 250 employees and $10.6 million in revenue. In 1978, Digital Communications Corp. was acquired by Microwave Associates for an undisclosed sum, becoming MA/COM-DCC and began developing satellite related products. The company invented the very small aperture terminal (VSAT) in 1985. That year, the company sold its first VSAT network to Wa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HS-376
The Boeing 376 (sometimes referred to as the BSS-376, and previously as the HS-376) is a communications satellite bus introduced in 1978 by Hughes Space and Communications Company. It was a spin-stabilized bus that the manufacturer claims was the first standardized platform. Design The satellite bus was designed and manufactured by Hughes. This spin-stabilized platform had two main sections. The spinning section was kept rotating at 50 rpm to maintain attitude, and a despun section was used by the payload to maintain radio coverage. The spinning section included the apogee kick motor, most of the attitude control, the power subsystem and the command and telemetry subsystems. The despun section contained the communications payload, including the antennas and transponders. The stock version had a launch mass of , a mass of after reaching geostationary orbit and an 8 to 10-year design life. When stowed for launch, its dimensions were in height and in diameter. With its sol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boeing Satellite Development Center
The Boeing Satellite Development Center is a major business unit of Boeing Defense, Space & Security. It brought together Boeing satellite operations with that of GM Hughes Electronics' Space and Communications division in El Segundo, California. History The facility was originally built by Nash Motors in 1946 and begun production in 1948, building the Nash Rambler. Howard Hughes' Hughes Aircraft Company formed the Aerospace Group within the company when they bought the facility in 1955, when the Nash company became American Motors Corporation and divided the facility into: * Hughes Space and Communications Group * Hughes Space Systems Division In 1953, the Howard Hughes Medical Institute (HHMI) was formed, and Hughes Aircraft reformed as a subsidiary of the foundation. The charity status of the foundation allowed Hughes Aircraft to avoid taxes on its huge income. In 1961, the two Aerospace Group divisions were reformed as Hughes Space and Communications Company. Hughes S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hughes Space And Communications Company
Hughes may refer to: People * Hughes (surname) * Hughes (given name) Places Antarctica * Hughes Range (Antarctica), Ross Dependency * Mount Hughes, Oates Land * Hughes Basin, Oates Land * Hughes Bay, Graham Land * Hughes Bluff, Victoria Land * Hughes Glacier, Victoria Land * Hughes Island, Victoria Land * Hughes Peninsula, Ellsworth Land * Hughes Point, Ellsworth Land Australia * Division of Hughes, an electoral district * Hughes, Australian Capital Territory, a suburb of Canberra * Hughes, Northern Territory, a rural locality United States * Hughes, Alaska, a city * Hughes, Arkansas, a city * Hughes, Iowa, a ghost town * Hughes, Wisconsin, a town * Hughes County, Oklahoma * Hughes County, South Dakota * Hughes Lake (California) * Hughes Mountain, Missouri * Hughes River (Virginia) * Hughes River (West Virginia) Other * Hughes, Santa Fe, Argentina, a town * Hughes Range (British Columbia), Canada * Hughes Reef, South China Sea * 1878 Hughes, an asteroid Businesses ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ku Band
The Ku band () is the portion of the electromagnetic spectrum in the microwave range of frequencies from 12 to 18 gigahertz (GHz). The symbol is short for "K-under" (originally german: Kurz-unten), because it is the lower part of the original NATO K band, which was split into three bands (Ku, K, and Ka) because of the presence of the atmospheric water vapor resonance peak at 22.24 GHz, (1.35 cm) which made the center unusable for long range transmission. In radar applications, it ranges from 12 to 18 GHz according to the formal definition of radar frequency band nomenclature in IEEE Standard 521–2002. Ku band is primarily used for satellite communications, most notably the downlink used by direct broadcast satellites to broadcast satellite television, and for specific applications such as NASA's Tracking Data Relay Satellite used for International Space Station (ISS) communications and SpaceX Starlink satellites. Ku band satellites are also used for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Satellite Business Systems
Satellite Business Systems (SBS) was a company founded by IBM, Aetna, COMSAT (and later wholly purchased by IBM and then subsequently sold to MCI), that provided private professional satellite communications through its SBS fleet of FSS geosynchronous satellites, and was the first company to do so. SBS was founded on December 15, 1975 by the aforementioned companies with the goal of providing a digital satellite communications network for business and other professional clients. History In late 1970, MCI Communications created a subsidiary company named MCI Satellite, Inc. The idea was that satellites could provide 'long distance' service from anywhere to anywhere without having to build thousands of miles of terrestrial network facilities. In early 1971, MCI and Lockheed Missiles and Space Company created a joint venture named MCI Lockheed Satellite Corp. which was the first company to request FCC authorization as a Specialized Common Carrier using satellite based communic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geostationary Orbit
A geostationary orbit, also referred to as a geosynchronous equatorial orbit''Geostationary orbit'' and ''Geosynchronous (equatorial) orbit'' are used somewhat interchangeably in sources. (GEO), is a circular geosynchronous orbit in altitude above Earth's equator ( in radius from Earth's center) and following the direction of Earth's rotation. An object in such an orbit has an orbital period equal to Earth's rotational period, one sidereal day, and so to ground observers it appears motionless, in a fixed position in the sky. The concept of a geostationary orbit was popularised by the science fiction writer Arthur C. Clarke in the 1940s as a way to revolutionise telecommunications, and the first satellite to be placed in this kind of orbit was launched in 1963. Communications satellites are often placed in a geostationary orbit so that Earth-based satellite antennas do not have to rotate to track them but can be pointed permanently at the position in the sky where the sat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
