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Amazonas 1
Amazonas 1 or Hispasat 55W-1 was a communications satellite based on the Eurostar 3000 satellite bus and owned by satellites operator Hispasat, based in Madrid, Spain. It was launched on 5 August 2004, with a launch mass of 4,5 ton, on a Proton-M Briz-M launcher to be located in the 61º W geostationary position. Amazonas 1 payloads were 36 Ku band transponders that provided communications services in Europe and America, and 27 C band transponders that provided services in America. In 2013 it was relocated to the 36º W position and replaced by Amazonas 3. In March 2016, Hispasat announced that Amazonas 1 would be renamed as Hispasat 55W-1. Finally, the satellite was moved to a 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 int ... and deactivated on 23 June 2017. ... [...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] |
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] |
2004 In Spain
The following lists events that happened during 2004 in Spain. Incumbents * Monarch: Juan Carlos I * Prime Minister: José María Aznar (until April 16), José Luis Rodríguez Zapatero (starting April 21) Events January February March * March 11 - Ten bombs explode on four trains in Madrid, leaving 191 dead and over 1000 injured. * March 12 - Millions of people pack rainswept streets across Spain in protest against the recent Madrid bombings. * March 14 - A general election is held in Spain. * March 14 - Spanish police receives a videotape where a man identifying himself as an al-Qaeda spokesman says the organisation claims responsibility for the attack, according to an announcement from the country's interior minister. The authenticity of the video has not been verified. The al-Qaeda claim overshadows voting in the general election. * March 15 - Newly elected Spanish Prime Minister José Luis Rodríguez Zapatero announces his government's opposition to the invasion and contin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Communications Satellites In Geostationary Orbit
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 non ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Communications Satellites
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 high frequency radio waves used for telecommunications links travel by Line-of-sight propagation, line of sight and so ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spacecraft Launched In 2004
A spacecraft is a vehicle or machine designed to fly in outer space. A type of artificial satellite, spacecraft are used for a variety of purposes, including communications, Earth observation, meteorology, navigation, space colonization, planetary exploration, and transportation of humans and cargo. All spacecraft except single-stage-to-orbit vehicles cannot get into space on their own, and require a launch vehicle (carrier rocket). On a sub-orbital spaceflight, a space vehicle enters outer space, space and then returns to the surface without having gained sufficient energy or velocity to make a full Earth orbit. For orbital spaceflights, spacecraft enter closed orbits around the Earth or around other Astronomical object, celestial bodies. Spacecraft used for human spaceflight carry people on board as crew or passengers from start or on orbit (space stations) only, whereas those used for robotic space missions operate either autonomous robot, autonomously or telerobotics, te ... [...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] |
Amazonas 3
Amazonas 3 is a communications satellite based on the SSL 1300 satellite bus and owned by the Hispasat Group of Madrid, Spain. It was launched by an Ariane 5 ECA launch vehicle on 7 February 2013, with a launch mass of 6265 kg. It will provide C-band and Ku-band service in Brazil for a joint venture of Hispasat Hispasat is the operating company for a number of Spanish communications satellites that cover the Americas, Europe and North Africa from orbital positions 30.0° West and 61.0° West. It was formed in 1989 and its activities include provision ... and the Brazilian telecommunications carrier Oi. References Spacecraft launched in 2013 Communications satellites in geostationary orbit 2013 in Spain Satellites of Spain Satellites using the SSL 1300 bus {{Spain-spacecraft-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
America
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territories, nine Minor Outlying Islands, and 326 Indian reservations. The United States is also in free association with three Pacific Island sovereign states: the Federated States of Micronesia, the Marshall Islands, and the Republic of Palau. It is the world's third-largest country by both land and total area. It shares land borders with Canada to its north and with Mexico to its south and has maritime borders with the Bahamas, Cuba, Russia, and other nations. With a population of over 333 million, it is the most populous country in the Americas and the third most populous in the world. The national capital of the United States is Washington, D.C. and its most populous city and principal financial center is New York City. Paleo-American ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transponder (satellite Communications)
A communications satellite's transponder is the series of interconnected units that form a communications channel between the receiving and the transmitting antennas. It is mainly used in satellite communication to transfer the received signals. A transponder is typically composed of: * an input band-limiting device (an input band-pass filter), * an input low-noise amplifier (LNA), designed to amplify the signals received from the Earth station (normally very weak, because of the large distances involved), * a frequency translator (normally composed of an oscillator and a frequency mixer) used to convert the frequency of the received signal to the frequency required for the transmitted signal, * an output band-pass filter, * a power amplifier (this can be a traveling-wave tube or a solid-state amplifier). Most communication satellites are radio relay stations in orbit and carry dozens of transponders, each with a bandwidth of tens of megahertz. Most transponders operate on a ... [...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] |
Madrid
Madrid ( , ) is the capital and most populous city of Spain. The city has almost 3.4 million inhabitants and a metropolitan area population of approximately 6.7 million. It is the second-largest city in the European Union (EU), and its monocentric metropolitan area is the third-largest in the EU.United Nations Department of Economic and Social AffairWorld Urbanization Prospects (2007 revision), (United Nations, 2008), Table A.12. Data for 2007. The municipality covers geographical area. Madrid lies on the River Manzanares in the central part of the Iberian Peninsula. Capital city of both Spain (almost without interruption since 1561) and the surrounding autonomous community of Madrid (since 1983), it is also the political, economic and cultural centre of the country. The city is situated on an elevated plain about from the closest seaside location. The climate of Madrid features hot summers and cool winters. The Madrid urban agglomeration has the second-large ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
