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Graves (system)
GRAVES (french: Grand Réseau Adapté à la Veille Spatiale) is a French radar-based space surveillance system, akin to the American Air Force Space Surveillance System. Using radar measurements, the French Air Force is able to spot satellites orbiting the Earth and determine their orbit. The GRAVES system took 15 years to develop, and became operational in November, 2005. GRAVES is also a contributing system to the European Space Agency's Space Situational Awareness Programme (SSA). GRAVES is a bistatic radar system using Doppler and directional information to derive the orbits of the detected satellites. Its operating frequency is 143.050 MHz, with the transmitter being located on a decommissioned airfield near Broye-lès-Pesmes at and the receiver at a former missile site near Revest du Bion on the Plateau d'Albion at . Data processing and generation of satellite orbital elements is performed at the Balard Air Complex in Paris, . See also * Space Situational Awareness Pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silo Du Plateau D'Albion
A silo (from the Greek σιρός – ''siros'', "pit for holding grain") is a structure for storing bulk materials. Silos are used in agriculture to store fermented feed known as silage, not to be confused with a grain bin, which is used to store grains. Silos are commonly used for bulk storage of grain, coal, cement, carbon black, woodchips, food products and sawdust. Three types of silos are in widespread use today: tower silos, bunker silos, and bag silos. Types of silos Tower silo Storage silos are cylindrical structures, typically 10 to 90 ft (3 to 27 m) in diameter and 30 to 275 ft (10 to 90 m) in height with the slipform and Jumpform concrete silos being the larger diameter and taller silos. They can be made of many materials. Wood staves, concrete staves, cast concrete, and steel panels have all been used, and have varying cost, durability, and airtightness tradeoffs. Silos storing grain, cement and woodchips are typically unloaded with air ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radar
Radar is a detection system that uses radio waves to determine the distance (''ranging''), angle, and radial velocity of objects relative to the site. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain. A radar system consists of a transmitter producing electromagnetic waves in the radio or microwaves domain, a transmitting antenna, a receiving antenna (often the same antenna is used for transmitting and receiving) and a receiver and processor to determine properties of the objects. Radio waves (pulsed or continuous) from the transmitter reflect off the objects and return to the receiver, giving information about the objects' locations and speeds. Radar was developed secretly for military use by several countries in the period before and during World War II. A key development was the cavity magnetron in the United Kingdom, which allowed the creation of relatively small systems with sub-meter resolution. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Air Force Space Surveillance System
The AN/FPS-133 Air Force Space Surveillance System, colloquially known as the Space Fence, was a U.S. government multistatic radar system built to detect orbital objects passing over America. It is a component of the U.S. space surveillance network, and according to the U.S. Navy was able to detect basketball sized () objects at heights up to . The system ceased operation in September 2013. Plans for a new space fence are underway with sites at the Kwajalein Atoll in the Marshall Islands, along with an option for another radar site in Western Australia. The operation's headquarters were at Dahlgren, Virginia, and radar stations were spread out across the continental United States at roughly the level of the 33rd parallel north. Description There were three transmitter sites in the system: * 216.983 MHz at Lake Kickapoo, Texas () (Master transmitter) * 216.970 MHz at Gila River, Arizona () * 216.990 MHz at Jordan Lake, Alabama () The master transmitter at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
French Air Force
The French Air and Space Force (AAE) (french: Armée de l'air et de l'espace, ) is the air and space force of the French Armed Forces. It was the first military aviation force in history, formed in 1909 as the , a service arm of the French Army; it became an independent military branch in 1934 as the French Air Force. On 10 September 2020, it assumed its current name, the French Air and Space Force, to reflect an "evolution of its mission" into the area of outer space. The number of aircraft in service with the French Air and Space Force varies depending on the source; the Ministry of Armed Forces gives a figure of 658 aircraft in 2014. According to 2018 data, this figure includes 210 combat aircraft: 115 Dassault Mirage 2000 and 95 Dassault Rafale. As of 2021, the French Air and Space Force employs a total of 40,500 regular personnel, with a reserve element of 5,187 in 2014. The Chief of Staff of the French Air and Space Force (CEMAAE) is a direct subordinate of the Chief of ... [...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] |
Orbit
In celestial mechanics, an orbit is the curved trajectory of an object such as the trajectory of a planet around a star, or of a natural satellite around a planet, or of an artificial satellite around an object or position in space such as a planet, moon, asteroid, or Lagrange point. Normally, orbit refers to a regularly repeating trajectory, although it may also refer to a non-repeating trajectory. To a close approximation, planets and satellites follow elliptic orbits, with the center of mass being orbited at a focal point of the ellipse, as described by Kepler's laws of planetary motion. For most situations, orbital motion is adequately approximated by Newtonian mechanics, which explains gravity as a force obeying an inverse-square law. However, Albert Einstein's general theory of relativity, which accounts for gravity as due to curvature of spacetime, with orbits following geodesics, provides a more accurate calculation and understanding of the exact mechanics of orbi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
European Space Agency
, owners = , headquarters = Paris, Île-de-France, France , coordinates = , spaceport = Guiana Space Centre , seal = File:ESA emblem seal.png , seal_size = 130px , image = Views in the Main Control Room (12052189474).jpg , size = , caption = , acronym = , established = , employees = 2,200 , administrator = Director General Josef Aschbacher , budget = €7.2 billion (2022) , language = English and French (working languages) , website = , logo = European Space Agency logo.svg , logo_caption = Logo , image_caption = European Space Operations Centre (ESOC) Main Control Room The European Space Agency (ESA; french: Agence spatiale européenne , it, Agenzia Spaziale Europea, es, Agencia Espacial Europea ASE; german: Europäische Weltraumorganisation) is an intergovernmental organisation of 22 member states dedicated to the exploration of space. Established in 1975 and headquartered i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Space Situational Awareness Programme
The Space Safety Programme, formerly the Space Situational Awareness (SSA) programme, is the European Space Agency's (ESA) initiative to monitor hazards from space, determine their risk, make this data available to the appropriate authorities and where possible, mitigate the threat. The SSA Programme was designed to support Europe's independent space access and utilization through the timely and accurate information delivery regarding the space environment, particularly hazards to both in-orbit and ground infrastructure. In 2019 it evolved into the present Space Safety Programme with an expanded focus, also including missions and activities to mitigate and prevent dangers from space. The programme is split into four main segments: * Space weather: monitoring the Sun, the solar wind, and in Earth's magnetosphere, ionosphere and thermosphere, that can affect spaceborne and ground-based infrastructure or endanger human life or health. This data is processed by thSpace Weather Service ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bistatic Radar
Bistatic radar is a radar system comprising a transmitter and receiver that are separated by a distance comparable to the expected target distance. Conversely, a conventional radar in which the transmitter and receiver are co-located is called a monostatic radar. A system containing multiple spatially diverse monostatic or bistatic radar components with a shared area of coverage is called ''multistatic radar''. Many long-range air-to-air and surface-to-air missile systems use semi-active radar homing, which is a form of bistatic radar. Types Pseudo-monostatic radars Some radar systems may have separate transmit and receive antennas, but if the angle subtended between transmitter, target and receiver (the bistatic angle) is close to zero, then they would still be regarded as monostatic or pseudo-monostatic. For example, some very long range HF radar systems may have a transmitter and receiver which are separated by a few tens of kilometres for electrical isolation, but as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Doppler Radar
A Doppler radar is a specialized radar that uses the Doppler effect to produce velocity data about objects at a distance. It does this by bouncing a microwave signal off a desired target and analyzing how the object's motion has altered the frequency of the returned signal. This variation gives direct and highly accurate measurements of the radial component of a target's velocity relative to the radar. Concept Doppler effect The Doppler effect (or Doppler shift), named after Austrian physicist Christian Doppler who proposed it in 1842, is the difference between the observed frequency and the emitted frequency of a wave for an observer moving relative to the source of the waves. It is commonly heard when a vehicle sounding a siren approaches, passes and recedes from an observer. The received frequency is higher (compared to the emitted frequency) during the approach, it is identical at the instant of passing by, and it is lower during the recession. This variation of f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Broye-lès-Pesmes
Broye-Aubigney-Montseugny () is a commune in the Haute-Saône department in the region of Bourgogne-Franche-Comté in eastern France.Commune de Broye-Aubigney-Montseugny (70101) INSEE The town was formed by the merger of Broye-lès-Pesmes, Aubigney, and Montseugny in 1972. Broye-lès-Pesmes has been proposed as the location of Amagetobria, a major settlement of the tribe in the pre-Roman and Roman era. Up to the 19th century, the town was called Moigte-de-Broie, which was derived from its ancient name. Gallery ...
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Revest Du Bion
In law, vesting is the point in time when the rights and interests arising from legal ownership of a property is acquired by some person. Vesting creates an immediately secured right of present or future deployment. One has a vested right to an asset that cannot be taken away by any third party, even though one may not yet possess the asset. When the right, interest, or title to the present or future possession of a legal estate can be transferred to any other party, it is termed a vested interest. The concept can arise in any number of contexts, but the most common are inheritance law and retirement plan law. In real estate, to vest is to create an entitlement to a privilege or a right. For example, one may cross someone else's property regularly and unrestrictedly for several years, and one's right to an easement becomes vested. The original owner still retains the possession, but can no longer prevent the other party from crossing. Inheritance Some bequests do not vest immedi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
