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UoSAT-5
UoSAT-5, also known as UoSAT-F, UO-22 and OSCAR 22, is a British satellite in Low Earth Orbit. It was built by Surrey Satellite Technology and launched into space in July 1991 from French Guiana. Mission UoSAT-5 carries equipment that was similar to that on UoSAT-4, a similar satellite that failed in orbit 1 year previously. The satellite tested new technologies, including validating the performance of 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, monoli ... solar arrays. References University of Surrey Satellites orbiting Earth Amateur radio satellites Satellites of the United Kingdom Spacecraft launched in 1991 {{UK-spacecraft-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Surrey Satellite Technology Ltd
Surrey Satellite Technology Ltd, or SSTL, is a company involved in the manufacture and operation of small satellites. A spin-off company of the University of Surrey, it is presently wholly owned by Airbus Defence and Space. The company began out of research efforts centred upon amateur radio satellites, known by the UoSAT (University of Surrey Satellite) name or by an OSCAR (Orbital Satellite Carrying Amateur Radio) designation. SSTL was founded in 1985, following successful trials on the use of commercial off-the-shelf (COTS) components on satellites, cumulating in the ''UoSat-1'' test satellite. It funds research projects with the university's Surrey Space Centre, which does research into satellite and space topics. In April 2008, the University of Surrey agreed to sell its majority share in the company to European multinational conglomerate EADS Astrium. In August 2008, SSTL opened a US subsidiary, which included both offices and a production site in Denver, Colorado; [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Surrey Satellite Technology
Surrey Satellite Technology Ltd, or SSTL, is a company involved in the manufacture and operation of small satellites. A spin-off company of the University of Surrey, it is presently wholly owned by Airbus Defence and Space. The company began out of research efforts centred upon amateur radio satellites, known by the UoSAT (University of Surrey Satellite) name or by an OSCAR (Orbital Satellite Carrying Amateur Radio) designation. SSTL was founded in 1985, following successful trials on the use of commercial off-the-shelf (COTS) components on satellites, cumulating in the ''UoSat-1'' test satellite. It funds research projects with the university's Surrey Space Centre, which does research into satellite and space topics. In April 2008, the University of Surrey agreed to sell its majority share in the company to European multinational conglomerate EADS Astrium. In August 2008, SSTL opened a US subsidiary, which included both offices and a production site in Denver, Colorado; [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
OSCAR
Oscar, OSCAR, or The Oscar may refer to: People * Oscar (given name), an Irish- and English-language name also used in other languages; the article includes the names Oskar, Oskari, Oszkár, Óscar, and other forms. * Oscar (Irish mythology), legendary figure, son of Oisín and grandson of Finn mac Cumhall Places * Oscar, Kentucky, an unincorporated community * Oscar, Louisiana, an unincorporated community * Oscar, Missouri, an unincorporated community * Oscar, Oklahoma, an unincorporated community * Oscar, Pennsylvania, an unincorporated community * Oscar, Texas, an unincorporated community * Oscar, West Virginia, an unincorporated community * Lake Oscar (other) * Oscar Township, Otter Tail County, Minnesota, a civil township Animals * Oscar (bionic cat), a cat that had implants after losing both hind paws * Oscar (bull), #16, (d. 1983) a ProRodeo Hall of Fame bucking bull * Oscar (fish), ''Astronotus ocellatus'' * Oscar (therapy cat), cat purported to pred ... [...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] |
Amateur Radio Satellites
An amateur () is generally considered a person who pursues an avocation independent from their source of income. Amateurs and their pursuits are also described as popular, informal, self-taught, user-generated, DIY, and hobbyist. History Historically, the amateur was considered to be the ideal balance between pure intent, open mind, and the interest or passion for a subject. That ideology spanned many different fields of interest. It may have its roots in the ancient Greek philosophy of amateur athletes competing in the Olympics. The ancient Greek citizens spent most of their time in other pursuits, but competed according to their natural talents and abilities. The "gentleman amateur" was a phenomenon among the gentry of Great Britain from the 17th century until the 20th century. With the start of the Age of Reason, with people thinking more about how the world works around them, (see science in the Age of Enlightenment), things like the cabinets of curiosities, and the wri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Satellites Orbiting Earth
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 transponders. Many satellites use a standardized bus to save cost and work, the most popular of which is small CubeSats. Similar satellites can work together as a group, forming 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 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 avoid orbital decay by the atmosphere. Satellites can then change or maintain the orbit by propulsion, ... [...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] |
French Guiana
French Guiana ( or ; french: link=no, Guyane ; gcr, label=French Guianese Creole, Lagwiyann ) is an overseas departments and regions of France, overseas department/region and single territorial collectivity of France on the northern Atlantic Ocean, Atlantic coast of South America in the Guianas. It borders Brazil to the east and south and Suriname to the west. With a land area of , French Guiana is the second-largest Regions of France, region of France (more than one-seventh the size of Metropolitan France) and the largest Special member state territories and the European Union, outermost region within the European Union. It has a very low population density, with only . (Its population is less than that of Metropolitan France.) Half of its 294,436 inhabitants in 2022 lived in the metropolitan area of Cayenne, its Prefectures in France, capital. 98.9% of the land territory of French Guiana is covered by forests, a large part of which is Old-growth forest, primeval Tropical r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Low Earth Orbit
A low Earth orbit (LEO) is an orbit around Earth with a period of 128 minutes or less (making at least 11.25 orbits per day) and an eccentricity less than 0.25. Most of the artificial objects in outer space are in LEO, with an altitude never more than about one-third of the radius of Earth. The term ''LEO region'' is also used for the area of space below an altitude of (about one-third of Earth's radius). Objects in orbits that pass through this zone, even if they have an apogee further out or are sub-orbital, are carefully tracked since they present a collision risk to the many LEO satellites. All crewed space stations to date have been within LEO. From 1968 to 1972, the Apollo program's lunar missions sent humans beyond LEO. Since the end of the Apollo program, no human spaceflights have been beyond LEO. Defining characteristics A wide variety of sources define LEO in terms of altitude. The altitude of an object in an elliptic orbit can vary significantly along the orbit. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sun-synchronous Orbit
A Sun-synchronous orbit (SSO), also called a heliosynchronous orbit, is a nearly polar orbit around a planet, in which the satellite passes over any given point of the planet's surface at the same local mean solar time. More technically, it is an orbit arranged so that it precesses through one complete revolution each year, so it always maintains the same relationship with the Sun. Applications A Sun-synchronous orbit is useful for imaging, reconnaissance, and weather satellites, because every time that the satellite is overhead, the surface illumination angle on the planet underneath it is nearly the same. This consistent lighting is a useful characteristic for satellites that image the Earth's surface in visible or infrared wavelengths, such as weather and spy satellites, and for other remote-sensing satellites, such as those carrying ocean and atmospheric remote-sensing instruments that require sunlight. For example, a satellite in Sun-synchronous orbit might ascend acros ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
University Of Surrey
The University of Surrey is a public research university in Guildford, Surrey, England. The university received its royal charter in 1966, along with a number of other institutions following recommendations in the Robbins Report. The institution was previously known as Battersea College of Technology and was located in Battersea Park, London. Its roots however, go back to Battersea Polytechnic Institute, founded in 1891 to provide further and higher education in London, including its poorer inhabitants. The university's research output and global partnerships have led to it being regarded as one of the UK's leading research universities. The university is a member of the Association of MBAs and is one of four universities in the University Global Partnership Network. It is also part of the SETsquared partnership along with the University of Bath, the University of Bristol, the University of Southampton and the University of Exeter. The university's main campus is on Stag Hi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geocentric Orbit
A geocentric orbit or Earth orbit involves any object orbiting Earth, such as the Moon or artificial satellites. In 1997, NASA estimated there were approximately 2,465 artificial satellite payloads orbiting Earth and 6,216 pieces of space debris as tracked by the Goddard Space Flight Center. More than 16,291 objects previously launched have undergone orbital decay and entered Earth's atmosphere. A spacecraft enters orbit when its centripetal acceleration due to gravity is less than or equal to the centrifugal acceleration due to the horizontal component of its velocity. For a low Earth orbit, this velocity is about ; by contrast, the fastest crewed airplane speed ever achieved (excluding speeds achieved by deorbiting spacecraft) was in 1967 by the North American X-15. The energy required to reach Earth orbital velocity at an altitude of is about 36 MJ/kg, which is six times the energy needed merely to climb to the corresponding altitude. Spacecraft with a perigee belo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
