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LARES (satellite)
LARES (Laser Relativity Satellite) is a passive satellite system of the Italian Space Agency. Mission Launch LARES was launched into orbit on 13 February 2012 at 10:00:00 UTC. It was launched on the first Vega rocket from the ESA Centre Spatial Guyanais in Kourou, French Guiana. Composition The satellite is made of THA-18N, a tungsten alloy, and houses 92 cube-corner retroreflectors, which are used to track the satellite via laser from stations on Earth. LARES's body has a diameter of about and a mass of about . LARES was inserted in a nearly circular orbit near and an inclination of 69.49 degrees. The satellite is tracked by the International Laser Ranging Service stations. The LARES satellite is the densest object known orbiting the Earth. The high density helps reduce disturbances from environmental factors such as solar radiation pressure. Scientific goals The main scientific target of the LARES mission is the measurement of the Lense–Thirring effect with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Satellite Laser Ranging
In satellite laser ranging (SLR) a global network of observation stations measures the round trip time of flight of ultrashort pulses of light to satellites equipped with retroreflectors. This provides instantaneous range measurements of millimeter level precision which can be accumulated to provide accurate measurement of orbits and a host of important scientific data. The laser pulse can also be reflected by the surface of a satellite without a retroreflector, which is used for tracking space debris. Satellite laser ranging is a proven geodetic technique with significant potential for important contributions to scientific studies of the earth/atmosphere/ocean system. It is the most accurate technique currently available to determine the geocentric position of an Earth satellite, allowing for the precise calibration of radar altimeters and separation of long-term instrumentation drift from secular changes in ocean topography. Its ability to measure the variations over time in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lense–Thirring Precession
In general relativity, Lense–Thirring precession or the Lense–Thirring effect (; named after Josef Lense and Hans Thirring) is a Theory of relativity, relativistic correction to the precession of a gyroscope near a large rotating mass such as the Earth. It is a gravitomagnetism, gravitomagnetic frame-dragging effect. It is a prediction of general relativity consisting of secular variation, secular precessions of the longitude of the ascending node and the argument of pericenter of a test particle freely orbiting a central spinning mass endowed with angular momentum S. The difference between de Sitter precession and the Lense–Thirring effect is that the de Sitter effect is due simply to the presence of a central mass, whereas the Lense–Thirring effect is due to the rotation of the central mass. The total precession is calculated by combining the de Sitter precession with the Lense–Thirring precession. According to a 2007 historical analysis by Herbert Pfister, the effect ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vega-C
Vega ( it, Vettore Europeo di Generazione Avanzata, or french: Vecteur européen de génération avancée, or en, European Vector of Advanced Generation, meaning "Advanced generation European carrier rocket") is an expendable launch system in use by Arianespace jointly developed by the Italian Space Agency (ASI) and the European Space Agency (ESA). Development began in 1998 and the first launch took place from the Guiana Space Centre, Centre Spatial Guyanais on 13 February 2012. It is designed to launch small payloads – 300 to 2500 kg satellites for scientific and Earth observation satellite, Earth observation missions to Polar orbit, polar and Low Earth orbit, low Earth orbits. The reference Vega mission is a polar orbit bringing a spacecraft of 1500 kg to an altitude of 700 km. The rocket, named after Vega, the List of brightest stars, brightest star in the constellation Lyra, is a single-body launcher (no strap-on boosters) with three Solid-propellant rocke ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
