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Intelsat 5
Intelsat 5 (IS-5, PAS-5, Arabsat 2C) was a satellite providing television and communication services for Intelsat, which it was commissioned by in 2006. Satellite description It was manufactured by Hughes Space and Communications. At beginning of life, it generates nearly 10 kilowatts. This version takes advantage of such advances as dual-junction gallium arsenide solar cells, new battery technology and the first commercial use of a high-efficiency xenon ion propulsion system (XIPS). PanAmSat became HSC's first customer to launch the new model, on 28 August 1997, at 00:33:30 UTC, on a Russian Proton-K / Blok DM-2M launch vehicle from the Baikonur Cosmodrome in Kazakhstan. PAS-5 provides satellite services in the Americas, with access to Europe, including direct-to-home (DTH) television services in Mexico. Controllers began noticing degradation of the nickel–hydrogen battery in PAS-5 earlier in 1998. The effect on operations was analyzed in June 1998. During periods of pea ... [...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] |
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] |
Kazakhstan
Kazakhstan, officially the Republic of Kazakhstan, is a transcontinental country located mainly in Central Asia and partly in Eastern Europe. It borders Russia to the north and west, China to the east, Kyrgyzstan to the southeast, Uzbekistan to the south, and Turkmenistan to the southwest, with a coastline along the Caspian Sea. Its capital is Astana, known as Nur-Sultan from 2019 to 2022. Almaty, Kazakhstan's largest city, was the country's capital until 1997. Kazakhstan is the world's largest landlocked country, the largest and northernmost Muslim-majority country by land area, and the ninth-largest country in the world. It has a population of 19 million people, and one of the lowest population densities in the world, at fewer than 6 people per square kilometre (15 people per square mile). The country dominates Central Asia economically and politically, generating 60 percent of the region's GDP, primarily through its oil and gas industry; it also has vast mineral ... [...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] |
Ion Thruster
An ion thruster, ion drive, or ion engine is a form of electric propulsion used for spacecraft propulsion. It creates thrust by accelerating ions using electricity. An ion thruster ionizes a neutral gas by extracting some electrons out of atoms, creating a cloud of positive ions. Ion thrusters are categorized as either electrostatic or electromagnetic. Electrostatic thruster ions are accelerated by the Coulomb force along the electric field direction. Temporarily stored electrons are reinjected by a ''neutralizer'' in the cloud of ions after it has passed through the electrostatic grid, so the gas becomes neutral again and can freely disperse in space without any further electrical interaction with the thruster. By contrast, electromagnetic thruster ions are accelerated by the Lorentz force to accelerate all species (free electrons as well as positive and negative ions) in the same direction whatever their electric charge, and are specifically referred to as plasma prop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solar Cell
A solar cell, or photovoltaic cell, is an electronic device that converts the energy of light directly into electricity by the photovoltaic effect, which is a physical and chemical phenomenon.Solar Cells chemistryexplained.com It is a form of photoelectric cell, defined as a device whose electrical characteristics, such as , , or resistance, vary when exposed to light. Individual solar cell devices are often the electrical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gallium Arsenide
Gallium arsenide (GaAs) is a III-V direct band gap semiconductor with a Zincblende (crystal structure), 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 process, Czoch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Satellite
A satellite or artificial satellite is an object intentionally placed into orbit in outer space. Except for passive satellites, most satellites have an electricity generation system for equipment on board, such as solar panels or radioisotope thermoelectric generators (RTGs). Most satellites also have a method of communication to ground stations, called Transponder (satellite communications), transponders. Many satellites use a Satellite bus, standardized bus to save cost and work, the most popular of which is small CubeSats. Similar satellites can work together as a group, forming Satellite constellation, constellations. Because of the high launch cost to space, satellites are designed to be as lightweight and robust as possible. Most communication satellites are radio Broadcast relay station, relay stations in orbit and carry dozens of transponders, each with a bandwidth of tens of megahertz. Satellites are placed from the surface to orbit by launch vehicles, high enough to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intelsat 7
Intelsat 7, formerly PAS-7, was a communications satellite operated by Intelsat which spent most of its operational life serving the Europe, Africa, Middle East, Asia market from a longitude of 18° West. Satellite description PAS-7 was constructed by Space Systems/Loral, based on the LS-1300 satellite bus. It had a mass at launch of . Designed for an operational life of 15 years, the spacecraft was equipped with 14 C-band at 50 watts and 30 Ku-band at 100 watts transponders. Launch Arianespace launched PAS-7, using an Ariane 4 launch vehicle, flight number V98, in the Ariane 44LP H10-3 configuration. The launch took place from ELA-2 at the Centre Spatial Guyanais, at Kourou in French Guiana, on 16 September 1998, at 06:31 UTC. Decommissioning PAS-7 experienced a sudden reduction of approximately 25% of its power capacity because a technical difficulty with one of the satellite's solar panels. The incident took place on 6 September 2001 when the satellite came out o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PAS-6
PAS-6 was a communications satellite owned by PanAmSat and serving the South America market. Satellite description PAS-6 was constructed by Space Systems/Loral, based on the LS-1300 satellite bus. It had a mass at launch of . Designed for an operational life of 15 years, the spacecraft was equipped with 36 Ku-band transponders. Launch Arianespace launched PAS-6, using an Ariane 4 launch vehicle, flight number V98, in the Ariane 44P H10-3 configuration. The launch took place from ELA-2 at the Centre Spatial Guyanais, at Kourou in French Guiana, on 8 August 1997, at 06:46:00 UTC. Decommissioning On 17 March 2004, PAS-6 suffered an anomaly resulting in a loss of power. Then PanAmSat moved the satellite to a storage orbit while the PanAmSat and SS/L evaluated the problem. On 1 April 2004, this satellite experienced another anomaly and more significant loss of power. PAS-6 was put in graveyard orbit A graveyard orbit, also called a junk orbit or disposal orbit, is an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asia-Pacific
Asia-Pacific (APAC) is the part of the world near the western Pacific Ocean. The Asia-Pacific region varies in area depending on context, but it generally includes East Asia, Russian Far East, South Asia, Southeast Asia, Australia and Pacific Islands. Definition The term may include countries in North America and South America that are on the coast of the Eastern Pacific Ocean; the Asia-Pacific Economic Cooperation, for example, includes Canada, Chile, Mexico, Peru, and the United States. Alternatively, the term sometimes comprises all of Asia and Australasia as well as Pacific island nations (Asia-Pacific and Australian continent)—for example, when dividing the world into large regions for commercial purposes (e.g., into APAC, EMEA, LATAM, and NA). Central Asia and Western Asia are almost never included. [...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 Afr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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