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DFS Kopernikus-3
DFS Kopernikus-3 (or Deutscher Fernmelde Satellit-3 and Hellas Sat 1) was a communications satellite operated by Deutsche Telekom. Satellite description The DFS Kopernikus series of satellites debuted in 1989 with the third being launched in 1992. Ordered in 1983 and produced by the GESAT consortium of MBB (flight segment prime contractor), Siemens (overall prime contractor), ANT Nachrichtentechnik (payload), Standard Elektrik Lorenz (digital switching equipment), and Dornier Systems (ground control system), DFS spacecraft are smaller than TV-Sat: on-station mass is 850 kg with a 15.4 m solar array span providing up to 1.5 kW of electrical power. The satellite also used a propulsion system S400. The communications payload includes ten 14/11-12 GHz transponders with five spares and one experimental 30/20 GHz transponder with one spare. At the end of 1994, DFS 1-3 were stationed at 33.5° East, 28.5° East, and 23.5° East, respectively. Like TV-Sat, the DFS K ... [...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] |
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] |
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 pad, launch pads, supported by a missile launch control center, 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 spaceflight, 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 spaceflight, 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-propellant rocket, solid fuel, liquid hydrogen, kerosene, liquid oxygen, or Hypergolic propellants. Launch vehicles are cla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Greece
Greece,, or , romanized: ', officially the Hellenic Republic, is a country in Southeast Europe. It is situated on the southern tip of the Balkans, and is located at the crossroads of Europe, Asia, and Africa. Greece shares land borders with Albania to the northwest, North Macedonia and Bulgaria to the north, and Turkey to the northeast. The Aegean Sea lies to the east of the Geography of Greece, mainland, the Ionian Sea to the west, and the Sea of Crete and the Mediterranean Sea to the south. Greece has the longest coastline on the Mediterranean Basin, featuring List of islands of Greece, thousands of islands. The country consists of nine Geographic regions of Greece, traditional geographic regions, and has a population of approximately 10.4 million. Athens is the nation's capital and List of cities and towns in Greece, largest city, followed by Thessaloniki and Patras. Greece is considered the cradle of Western culture, Western civilization, being the birthplace of Athenian ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hertz
The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), equivalent to one event (or cycle) per second. The hertz is an SI derived unit whose expression in terms of SI base units is s−1, meaning that one hertz is the reciprocal of one second. It is named after Heinrich Rudolf Hertz (1857–1894), the first person to provide conclusive proof of the existence of electromagnetic waves. Hertz are commonly expressed in multiples: kilohertz (kHz), megahertz (MHz), gigahertz (GHz), terahertz (THz). Some of the unit's most common uses are in the description of periodic waveforms and musical tones, particularly those used in radio- and audio-related applications. It is also used to describe the clock speeds at which computers and other electronics are driven. The units are sometimes also used as a representation of the energy of a photon, via the Planck relation ''E'' = ''hν'', where ''E'' is the photon's energy, ''ν'' is its freq ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
S400 (rocket Engine)
The S400 is a family of pressure fed liquid propelled rocket engines manufactured by ArianeGroup (former Airbus DS) at the Orbital Propulsion Centre in Lampoldshausen, Germany. They burn MMH and MON as propellant, have a thrust range between and and can vary the O/F ratio between 1.50 and 1.80. The chamber and throat are made of a platinum alloy, it uses double cone vortex injectors and uses both film and radiative cooling. The S400 engines are used as primary apogee engines for telecommunication satellite platforms such as the Spacebus of Thales Alenia Space as well as space exploration missions such as Venus Express, ExoMars Trace Gas Orbiter or Jupiter Icy Moons Explorer. The S400 family has had an extensive history on the commercial telecommunication market. Its first launch was aboard the Symphonie 1 in 1974. This was the first commercial three-axis stabilized communications satellite in geostationary orbit with a bipropellant rocket propulsion system. It also wa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Watt
The watt (symbol: W) is the unit of power or radiant flux in the International System of Units (SI), equal to 1 joule per second or 1 kg⋅m2⋅s−3. It is used to quantify the rate of energy transfer. The watt is named after James Watt (1736–1819), an 18th-century Scottish inventor, mechanical engineer, and chemist who improved the Newcomen engine with his own steam engine in 1776. Watt's invention was fundamental for the Industrial Revolution. Overview When an object's velocity is held constant at one metre per second against a constant opposing force of one newton, the rate at which work is done is one watt. : \mathrm In terms of electromagnetism, one watt is the rate at which electrical work is performed when a current of one ampere (A) flows across an electrical potential difference of one volt (V), meaning the watt is equivalent to the volt-ampere (the latter unit, however, is used for a different quantity from the real power of an electrical circuit). : ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TV-SAT 1
TV-SAT 1 or TVSAT-1 was a West German communications satellite, which was to have been operated by Deutsche Bundespost. It was intended to provide television broadcast services to Europe, but it failed before entering service. It was built by Aérospatiale, was based on the Spacebus 300 satellite bus, and carried five Ku-band transponders. At launch it had a mass of , and an expected operational lifespan of eight years. Launch TV-SAT 1 was launched by Arianespace using an Ariane 2 rocket flying from ELA-2 at Centre Spatial Guyanais, Kourou, French Guiana. The launch took place at 02:19:00 UTC on 21 November 1987. It was the first Spacebus 300 satellite to be launched. Immediately after launch, one of its solar panels failed to deploy, so that the main uplink antenna, behind the solar panel, could not deploy either. This failure was caused by the presence of two hold-down bolts, which should have been removed before launch. Mission Despite the failure, TV-SAT 1 was placed in ... [...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] |
DFS Kopernicus-2
DFS may refer to: Brands and enterprises * Dancer Fitzgerald Sample, advertising agency, now Saatchi & Saatchi * DFS Furniture, a furniture retailer in the United Kingdom and Ireland * DFS Group (Duty Free Shoppers), Hong Kong * DFS Program Exchange, a former syndicator of TV programs * Discover Financial Services, NYSE symbol Organizations * Department of Field Support, a UN department * Department of Financial Services (other) * Department of Financial Studies, University of Delhi, India * Det frivillige Skyttervesen, the National Rifle Association of Norway * Deutsche Flugsicherung, the German air traffic control organisation * Deutsche Forschungsanstalt für Segelflug (German Research Institute for Sailplane Flight) * Dirección Federal de Seguridad, Federal Direction of Security, Mexico * New York State Department of Financial Services Science and technology Computing * Depth-first search, an algorithm for traversing or searching tree or graph data structures * Disc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DFS Kopernikus
DFS Kopernikus (meaning ''Deutscher Fernmeldesatellit Kopernikus'') was the name of three geostationary satellites of Deutsche Bundespost and later Deutsche Telekom AG. They are no longer in use. DFS Kopernicus-3 When DFS Kopernikus-3 was nearing the end of its life, SES sealed an agreement with Deutsche Telekom to use the 23.5° East position and frequencies, and in August 2001, Astra 1D was moved there."New position for ASTRA 1D" ''Advanced Television'' (21 August 2001) Retrieved on 17 April 2021 The position was officially opened in March 2002 with the launch and positioning of [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Germany
Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated between the Baltic and North seas to the north, and the Alps to the south; it covers an area of , with a population of almost 84 million within its 16 constituent states. Germany borders Denmark to the north, Poland and the Czech Republic to the east, Austria and Switzerland to the south, and France, Luxembourg, Belgium, and the Netherlands to the west. The nation's capital and most populous city is Berlin and its financial centre is Frankfurt; the largest urban area is the Ruhr. Various Germanic tribes have inhabited the northern parts of modern Germany since classical antiquity. A region named Germania was documented before AD 100. In 962, the Kingdom of Germany formed the bulk of the Holy Roman Empire. During the 16th ce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
