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Sazhen-S
Sazhen-S () is a Soviet The Union of Soviet Socialist Republics. (USSR), commonly known as the Soviet Union, was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 until Dissolution of the Soviet ... laser/optical space surveillance system, used to analyse the orbital parameters of spacecraft. There are several installations across the former Soviet Union, one of which is based at space ground station NIP-19The official English name is the Centre of the special information receiving and processing and the navigating field control. NIP-19 is its former Soviet name. near Dunaivtsi in Ukraine. It is named after the ''sazhen'', a former Russian units of measurement, Russian unit of measurement that translates as fathom and has a length of . A similar system is Sazhen-T. History A number of Sazhen-S installations were constructed at the network of scientific monitoring stations. At least two are now in Ukraine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Space Surveillance
Space domain awareness is the study and monitoring of satellites orbiting the Earth. It involves the detection, tracking, cataloging and identification of artificial objects, i.e. active/inactive satellites, spent rocket bodies, or fragmentation debris. Aims Space domain awareness accomplishes the following: * Predicting when and where a decaying space object will re-enter the Earth's atmosphere; * Preventing a returning space object, which to radar looks like a missile, from triggering a false alarm in missile-attack warning sensors; * Charting the present position of space objects and plot their anticipated orbital paths; * Detecting new human-made objects in space; * Producing a running catalogue of human-made space objects; * Determining which country owns a re-entering space object; * Informing countries whether or not objects may interfere with satellites and International Space Station The International Space Station (ISS) is a large space station that was Asse ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vityne
Vityne (; ) is a village ('' selo'') in Saky Raion (district) in the Autonomous Republic of Crimea, on the western coast of Crimea. Demographics As of the 2001 Ukrainian census, the settlement had 867 inhabitants, whose native languages were 20.72% Ukrainian, 76.55% Russian, 3.10% Crimean Crimea ( ) is a peninsula in Eastern Europe, on the northern coast of the Black Sea, almost entirely surrounded by the Black Sea and the smaller Sea of Azov. The Isthmus of Perekop connects the peninsula to Kherson Oblast in mainland Ukrai ..., 0.39% Belarusian and 0.10% Gagauz. References Villages in Crimea {{Crimea-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cassegrain Reflector
The Cassegrain reflector is a combination of a primary concave mirror and a secondary convex mirror, often used in optical telescopes and Antenna (radio), radio antennas, the main characteristic being that the optical path folds back onto itself, relative to the optical system's primary mirror entrance aperture. This design puts the Focus (optics), focal point at a convenient location behind the primary mirror and the convex secondary adds a Telephoto lens, telephoto effect creating a much longer focal length in a mechanically short system. In a symmetrical Cassegrain both mirrors are aligned about the optical axis, and the primary mirror usually contains a hole in the center, thus permitting the light to reach an eyepiece, a camera, or an image sensor. Alternatively, as in many radio telescopes, the final focus may be in front of the primary. In an asymmetrical Cassegrain, the mirror(s) may be tilted to avoid obscuration of the primary or to avoid the need for a hole in the prima ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apparent Magnitude
Apparent magnitude () is a measure of the Irradiance, brightness of a star, astronomical object or other celestial objects like artificial satellites. Its value depends on its intrinsic luminosity, its distance, and any extinction (astronomy), extinction of the object's light caused by interstellar dust along the sightline, line of sight to the observer. Unless stated otherwise, the word ''magnitude'' in astronomy usually refers to a celestial object's apparent magnitude. The magnitude scale likely dates to before the ancient Ancient Greek astronomy#Astronomy in the Greco-Roman and Late Antique eras, Roman astronomer Ptolemy, Claudius Ptolemy, whose Star catalogue, star catalog popularized the system by listing stars from First-magnitude star, 1st magnitude (brightest) to 6th magnitude (dimmest). The modern scale was mathematically defined to closely match this historical system by Norman Robert Pogson, Norman Pogson in 1856. The scale is reverse logarithmic scale, logarithmic: ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Angle
In Euclidean geometry, an angle can refer to a number of concepts relating to the intersection of two straight Line (geometry), lines at a Point (geometry), point. Formally, an angle is a figure lying in a Euclidean plane, plane formed by two Ray (geometry), rays, called the ''Side (plane geometry), sides'' of the angle, sharing a common endpoint, called the ''vertex (geometry), vertex'' of the angle. More generally angles are also formed wherever two lines, rays or line segments come together, such as at the corners of triangles and other polygons. An angle can be considered as the region of the plane bounded by the sides. Angles can also be formed by the intersection of two planes or by two intersecting curves, in which case the rays lying tangent to each curve at the point of intersection define the angle. The term ''angle'' is also used for the size, magnitude (mathematics), magnitude or Physical quantity, quantity of these types of geometric figures and in this context an a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geosynchronous Orbit
A geosynchronous orbit (sometimes abbreviated GSO) is an Earth-centered orbit with an orbital period that matches Earth's rotation on its axis, 23 hours, 56 minutes, and 4 seconds (one sidereal day). The synchronization of rotation and orbital period means that, for an observer on Earth's surface, an object in geosynchronous orbit returns to exactly the same position in the sky after a period of one sidereal day. Over the course of a day, the object's position in the sky may remain still or trace out a path, typically in a figure-8 form, whose precise characteristics depend on the orbit's inclination and eccentricity. A circular geosynchronous orbit has a constant altitude of . A special case of geosynchronous orbit is the geostationary orbit (often abbreviated ''GEO''), which is a circular geosynchronous orbit in Earth's equatorial plane with both inclination and eccentricity equal to 0. A satellite in a geostationary orbit remains in the same position in the sky to observers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Low Earth Orbit
A low Earth orbit (LEO) is an geocentric orbit, orbit around Earth with a orbital period, period of 128 minutes or less (making at least 11.25 orbits per day) and an orbital eccentricity, eccentricity less than 0.25. Most of the artificial objects in outer space are in LEO, peaking in number at an altitude around , while the farthest in LEO, before medium Earth orbit (MEO), have an altitude of 2,000 km, about one-third of the Earth radius, radius of Earth and near the beginning of the Van Allen radiation belt#Inner belt, inner Van Allen radiation belt. The term ''LEO region'' is 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 spaceflight, sub-orbital, are carefully tracked since they present a collision risk to the many LEO satellites. No human spaceflights other than the lunar missions of the Apollo program (1968-1972) have gone beyond L ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corner Reflector
A corner reflector is a retroreflector consisting of three mutually perpendicular, intersecting flat reflective surfaces. It reflects waves incident from any direction directly towards the source, but translated. The three intersecting surfaces often are triangles (forming a tetrahedron) or may have square shapes. Radar corner reflectors made of metal are used to reflect radio waves from radar sets. Optical corner reflectors, called corner cubes or cube corners, made of three-sided glass prisms, are used in surveying and laser ranging. Principle The incoming ray is reflected three times, once by each surface, which results in a reversal of direction. To see this, the three corresponding normal vectors of the corner's perpendicular sides can be considered to form a basis (a rectangular coordinate system) (''x'', ''y'', ''z'') in which to represent the direction of an arbitrary incoming ray, . When the ray reflects from the first side, say ''x'', the ray's ''x'' compon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Slant Range
In radio electronics, especially radar terminology, slant range or slant distance is the distance along the relative direction (geometry), relative direction between two points. If the two points are at the same level (coordinate), level (relative to a specific Datum (geodesy), datum), the slant distance equals the horizontal distance. An example of slant range is the distance to an aircraft flying at high altitude with respect to that of the radar antenna (electronics), antenna. The slant range (1) is the hypotenuse of the triangle represented by the altitude of the aircraft and the distance between the radar antenna and the aircraft's Course (navigation), ground track (point (3) on the earth directly below the aircraft). In the absence of altitude information, for example from a height finder, the aircraft location would be plotted further (2) from the antenna than its actual ground track. See also *Ranging *Spherical range *Line-of-sight_propagation References * * Ant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laser Ranging
A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation. The word ''laser'' originated as an acronym for light amplification by stimulated emission of radiation. The first laser was built in 1960 by Theodore Maiman at Hughes Research Laboratories, based on theoretical work by Charles H. Townes and Arthur Leonard Schawlow and the optical amplifier patented by Gordon Gould. A laser differs from other sources of light in that it emits light that is ''coherent''. Spatial coherence allows a laser to be focused to a tight spot, enabling uses such as optical communication, laser cutting, and lithography. It also allows a laser beam to stay narrow over great distances (collimation), used in laser pointers, lidar, and free-space optical communication. Lasers can also have high temporal coherence, which permits them to emit light with a very narrow frequency spectrum. Temporal coherence can also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yevpatoria
Yevpatoria (; ; ; ) is a city in western Crimea, north of Kalamita Bay. Yevpatoria serves as the administrative center of Yevpatoria Municipality, one of the districts (''raions'') into which Crimea is divided. It had a population of History Greek settlement The first recorded settlement in the area, called ''Kerkinitis'' (), was built by Greek colonists around 500 BCE. Along with the rest of the Crimea, Kerkinitis formed part of the dominions of King Mithridates VI Eupator ( BCE). The name of the modern city derives from his nickname, ''Eupator'' ('of a noble father'). Khanate period From roughly the 7th through the 10th centuries, Yevpatoria was a Khazar settlement; its name in Khazar language was probably ''Güzliev'' (literally 'beautiful house'). It was later subject to the Cumans ( Kipchaks), the Mongols, and the Crimean Khanate. During this period the city was called ''Kezlev'' by Crimean Tatars and ''Gözleve'' by Ottoman Turks. The Russian medieval ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Main Space Intelligence Centre
The 821st Main Centre for Reconnaissance of Situation in Space () is the headquarters of the Russian military's space surveillance network, SKKP. The centre is part of the Russian Space Forces and receives intelligence from a network of reporting stations which includes the Russian missile attack early warning network as well as some stations only used for space surveillance such as Okno and Krona. The purpose of the SKKP is to detect satellites, identify them and to discern their orbits. It maintains the Russian catalogue of space objects and provides data which could be used to support space launches, feed an anti-satellite programme and provide intelligence on hostile military satellites. It is the Russian equivalent of the United States Space Surveillance Network. History The centre is based in the military village of Noginsk-9 () about a kilometre to the south-west of the village of Dubrovo near Noginsk in Moscow Oblast. It was previously known as TsKKP (Цккп) from m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
