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Intelsat 33e
Intelsat 33e, also known as IS-33e, is a high throughput (HTS) geostationary communications satellite operated by Intelsat and designed and manufactured by Boeing Space Systems on the BSS 702MP satellite bus. It is the second satellite of the EpicNG service, and covers Europe, Africa and most of Asia from the 60° East longitude, where it replaced Intelsat 904. It has a mixed C-band, Ku-band and Ka-band payload with all bands featuring wide and C- and Ku- also featuring spot beams. Satellite description Intelsat 33e was designed and manufactured by Boeing on the Boeing 702MP satellite bus. It has a launch mass of and a design life of more than 15 years. When stowed for launch, the satellite measures . It is powered by two solar panels, with four panels each, of triple-junction GaAs solar cells. The 702MP platform was designed to generate between 6 kW and 12 kW, but Intelsat 33e is designed to generate 13 kW at the end of its design life. Its payload is the second high ... [...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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Central Africa
Central Africa is a subregion of the African continent comprising various countries according to different definitions. Angola, Burundi, the Central African Republic, Chad, the Democratic Republic of the Congo, the Republic of the Congo, Equatorial Guinea, Gabon, Rwanda, and São Tomé and Príncipe are members of the Economic Community of Central African States (ECCAS). Six of those states (the Central African Republic, Chad, the Republic of the Congo, Equatorial Guinea, and Gabon) are also members of the Economic and Monetary Community of Central Africa (CEMAC) and share a common currency, the Central African CFA franc. The African Development Bank defines Central Africa as the Central African Republic, Chad, the Democratic Republic of the Congo, the Republic of the Congo, Equatorial Guinea, and Gabon. Middle Africa is an analogous term used by the United Nations in its geoscheme for Africa. It includes the same countries as the African Development Bank's defin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gallium Arsenide
Gallium arsenide (GaAs) is a III-V direct band gap semiconductor with a zinc blende crystal structure. Gallium arsenide is used in the manufacture of devices such as microwave frequency integrated circuits, monolithic microwave integrated circuits, infrared light-emitting diodes, laser diodes, solar cells and optical windows. GaAs is often used as a substrate material for the epitaxial growth of other III-V semiconductors, including indium gallium arsenide, aluminum gallium arsenide and others. Preparation and chemistry In the compound, gallium has a +3 oxidation state. Gallium arsenide single crystals can be prepared by three industrial processes: * The vertical gradient freeze (VGF) process. * Crystal growth using a horizontal zone furnace in the Bridgman-Stockbarger technique, in which gallium and arsenic vapors react, and free molecules deposit on a seed crystal at the cooler end of the furnace. * Liquid encapsulated Czochralski (LEC) growth is used for producing hi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triple-junction Solar Cell
Multi-junction (MJ) solar cells are solar cells with multiple p–n junctions made of different semiconductor materials. Each material's p-n junction will produce electric current in response to different wavelengths of light. The use of multiple semiconducting materials allows the absorbance of a broader range of wavelengths, improving the cell's sunlight to electrical energy conversion efficiency. Traditional single-junction cells have a maximum theoretical efficiency of 33.16%. Theoretically, an infinite number of junctions would have a limiting efficiency of 86.8% under highly concentrated sunlight. As of 2008 the best lab examples of traditional crystalline silicon (c-Si) solar cells had efficiencies between 20% and 25%, while lab examples of multi-junction cells have demonstrated performance over 46% under concentrated sunlight. Commercial examples of tandem cells are widely available at 30% under one-sun illumination, and improve to around 40% under concentrated sunlight. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solar Panels On Spacecraft
Spacecraft operating in the inner Solar System usually rely on the use of power electronics-managed photovoltaic solar panels to derive electricity from sunlight. Outside the orbit of Jupiter, solar radiation is too weak to produce sufficient power within current solar technology and spacecraft mass limitations, so radioisotope thermoelectric generators (RTGs) are instead used as a power source.NASA JPL Publication: Basics of Space Flight, Chapter 11. Typical Onboard Systems, Electrical Power Supply and Distribution Subsystems, History The first practical silicon-based solar cells were introduced by Bell Labs in April 1954. They were initially about 6% efficient, but improvements began to raise this number almost immediately. Bell had been interested in the idea as a system to provide power at remote telephone repeater stations, but the cost of the devices was far too high to be practical in this role. Aside from small experimental kits and uses, the cells remained largely unus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intelsat 904
Intelsat 904 (or IS-904) is a communications satellite operated by Intelsat. Launch Intelsat 904 was launched by an Ariane 4 rocket from Guiana Space Centre, Kourou, French Guiana, at 06:59 UTC on February 23, 2002. Capacity and coverage The satellite will provide television and internet services to Europe, Asia and Australia through its 76 C band and 22 Ku band transponders after parking over 60 degrees east longitude. See also * 2002 in spaceflight External links * . Lyngsat * . Intelsat Intelsat S.A. (formerly INTEL-SAT, INTELSAT, Intelsat) is a multinational satellite services provider with corporate headquarters in Luxembourg and administrative headquarters in Tysons Corner, Virginia, United States. Originally formed as I ... References Intelsat satellites Communications satellites in geostationary orbit Ariane commercial payloads Spacecraft launched in 2002 {{US-spacecraft-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Africa
Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area and 20% of its land area.Sayre, April Pulley (1999), ''Africa'', Twenty-First Century Books. . With billion people as of , it accounts for about of the world's human population. Africa's population is the youngest amongst all the continents; the median age in 2012 was 19.7, when the worldwide median age was 30.4. Despite a wide range of natural resources, Africa is the least wealthy continent per capita and second-least wealthy by total wealth, behind Oceania. Scholars have attributed this to different factors including geography, climate, tribalism, colonialism, the Cold War, neocolonialism, lack of democracy, and corruption. Despite this low concentration of wealth, recent economic expansion and the large and young population make Afric ... [...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 ... [...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 ... [...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 s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intelsat 35e
Intelsat 35e, also known as IS-35e is an Intelsat high-throughput (HTS) geostationary communications satellite designed and manufactured by Boeing Satellite Systems on the Boeing-702MP satellite bus. It was launched on 5 July 2017. It is the fourth satellite of the EpicNG service and covers the Americas, Europe and Sub-Saharan Africa from the 34.5° West longitude. It has a mixed C-band and Ku-band, with the C-band featuring EpicNG spot beams. Satellite description Intelsat 35e was designed and manufactured by Boeing Satellite Systems on the Boeing 702MP satellite bus. It had a launch mass of , the largest Intelsat's currently active satellite, and has a design life of more than 15 years. It is powered by two wings, with four solar panels each, of triple-junction GaAs solar cells. The 702MP platform was designed to generate between 6 and 12 kW. Its payload was the fourth high-throughput EpicNG deployment. The EpicNG is characterized by the implementation of frequen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intelsat 29e
Intelsat 29e, also known as IS-29e was a high throughput (HTS) geostationary communications satellite designed and manufactured by Boeing Satellite Development Center on the BSS 702MP satellite bus. It is the first satellite of the EpicNG service, and covers North America and Latin America from the 50° West longitude, where it replaced Intelsat 1R. It also replaced Intelsat 805 which was moved from 56.5° West to 169° East. It has a mixed C-band, Ku-band and Ka-band payload with all bands featuring wide and the Ku- also featuring spot beams. Satellite description The spacecraft was designed and manufactured by Boeing Satellite Development Center on the Boeing 702MP satellite bus. It has a launch mass of and a design life of more than 15 years. When stowed for launch, the satellite measures . It is powered by two wings, with four solar panels each, of triple-junction GaAs solar cells, that span when deployed. Intelsat 29e can generate 15.8 kW at the end of its expect ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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