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Ukrainian Optical Facilities For Near-Earth Space Surveillance Network
Ukrainian Optical Facilities for Near-Earth Space Surveillance Network, the UMOS (from Ukrainian acronym: УМОС = ''Українська мережа оптичних станцій дослідження навколоземного космічного простору'') is an alliance of Ukrainian institutional research observatories and optical facilities of State Space Agency. Its strategic tasks include near-Earth space research (from LEO to HEO), and the studies of motion of selected objects by development and improvement of theory, models and algorithms. Also it is aimed at addressing tactical problems like assistance in Ukrainian or international space launches. The UMOS's field of view covers large area of space, its facilities arrangement allows to carry out the observations of 3-4 consecutive passes of LEO satellites, as well as synchronous and complementing observations. The UMOS has conducted the ground-based surveillance of Near-Earth objects since the establis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ukraine
Ukraine ( uk, Україна, Ukraïna, ) is a country in Eastern Europe. It is the second-largest European country after Russia, which it borders to the east and northeast. Ukraine covers approximately . Prior to the ongoing Russian invasion, it was the eighth-most populous country in Europe, with a population of around 41 million people. It is also bordered by Belarus to the north; by Poland, Slovakia, and Hungary to the west; and by Romania and Moldova to the southwest; with a coastline along the Black Sea and the Sea of Azov to the south and southeast. Kyiv is the nation's capital and largest city. Ukraine's state language is Ukrainian; Russian is also widely spoken, especially in the east and south. During the Middle Ages, Ukraine was the site of early Slavic expansion and the area later became a key centre of East Slavic culture under the state of Kievan Rus', which emerged in the 9th century. The state eventually disintegrated into rival regional po ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CryoSat-2
CryoSat-2 is a European Space Agency (ESA) Earth Explorer Mission that launched on April 8th 2010. CryoSat-2 is dedicated to measuring polar sea ice thickness and monitoring changes in ice sheets. Its primary objective is to measure the thinning of Arctic sea ice, but has applications to other regions and scientific purposes, such as Antarctica and oceanography. CryoSat-2 was built as a replacement for CryoSat-1, which failed to reach orbit following a launch failure in October 2005. CryoSat-2 was successfully launched five years later in 2010, with upgraded software aiming to measure changes in ice thickness to an accuracy of ~10% of the expected interannual variation. Unlike previous satellite altimetry missions, CryoSat-2 provides unparalleled Arctic coverage, reaching 88˚N (previous missions were limited to 81.5˚N). The primary payload of the mission is a synthetic aperture radar (SAR) Interferometric Radar Altimeter (SIRAL), which measures surface elevation. By subtracti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Space Observatory
A space telescope or space observatory is a telescope in outer space used to observe astronomical objects. Suggested by Lyman Spitzer in 1946, the first operational telescopes were the American Orbiting Astronomical Observatory, OAO-2 launched in 1968, and the Soviet Orion 1 ultraviolet telescope aboard space station Salyut 1 in 1971. Space telescopes avoid the filtering and distortion ( scintillation) of electromagnetic radiation which they observe, and avoid light pollution which ground-based observatories encounter. They are divided into two types: Satellites which map the entire sky (astronomical survey), and satellites which focus on selected astronomical objects or parts of the sky and beyond. Space telescopes are distinct from Earth imaging satellites, which point toward Earth for satellite imaging, applied for weather analysis, espionage, and other types of information gathering. History Wilhelm Beer and Johann Heinrich Mädler in 1837 discussed the advantages of ... [...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, 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 on the surface. Communicat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geostationary Orbit
A geostationary orbit, also referred to as a geosynchronous equatorial orbit''Geostationary orbit'' and ''Geosynchronous (equatorial) orbit'' are used somewhat interchangeably in sources. (GEO), is a circular geosynchronous orbit in altitude above Earth's equator ( in radius from Earth's center) and following the direction of Earth's rotation. An object in such an orbit has an orbital period equal to Earth's rotational period, one sidereal day, and so to ground observers it appears motionless, in a fixed position in the sky. The concept of a geostationary orbit was popularised by the science fiction writer Arthur C. Clarke in the 1940s as a way to revolutionise telecommunications, and the first satellite to be placed in this kind of orbit was launched in 1963. Communications satellites are often placed in a geostationary orbit so that Earth-based satellite antennas do not have to rotate to track them but can be pointed permanently at the position in the sky where the sat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Medium Earth Orbit
A medium Earth orbit (MEO) is an geocentric orbit, Earth-centered orbit with an altitude above a low Earth orbit (LEO) and below a high Earth orbit (HEO) – between above sea level.''Catalog of Earth Satellite Orbits'' NASA Earth Observatory. 4 September 2009. Accessed 2 May 2021. The boundary between MEO and LEO is an arbitrary altitude chosen by accepted convention, whereas the boundary between MEO and HEO is the particular altitude of a geosynchronous orbit, in which a satellite takes 24 hours to circle the Earth, the same period as the Earth’s own rotation. All satellites in MEO have an orbital period of less than 24 hours, with the minimum period (for a circular orbit at the lowest MEO altitude) about 2 hours. Satellites in MEO or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CubeSat
A CubeSat is a class of miniaturized satellite based around a form factor consisting of cubes. CubeSats have a mass of no more than per unit, and often use commercial off-the-shelf (COTS) components for their electronics and structure. CubeSats are put into orbit by deployers on the International Space Station, or launched as secondary payloads on a launch vehicle. , more than 1,600 CubeSats have been launched. In 1999, California Polytechnic State University (Cal Poly) professor Jordi Puig-Suari and Bob Twiggs, a professor at Stanford University Space Systems Development Laboratory, developed the CubeSat specifications to promote and develop the skills necessary for the design, manufacture, and testing of small satellites intended for low Earth orbit (LEO) that perform a number of scientific research functions and explore new space technologies. Academia accounted for the majority of CubeSat launches until 2013, when more than half of launches were for non-academic purposes, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orbcomm (satellite)
Orbcomm is a family of low Earth orbit communications satellites, operated by the United States satellite communications company Orbcomm. , 51 such satellites have orbited Earth, with 50 still continuing to do so. Satellite types Orbcomm-CDS Orbcomm-CDS (Concept or Capability Demonstration Satellites) are spacecraft which were launched to test equipment and communication techniques used by the other satellites. The first three CDS satellites, Orbcomm-X, CDS-1 and CDS-2, were launched before any operational satellites, in order to validate the systems to be used in the operational constellation. Orbcomm-X, also known as Datacomm-X, was launched in 1991. It carried communications and GPS experiments. Initially, the spacecraft was reported healthy, but communication was lost after just one orbit. CDS-3 was launched in 2008, along with the 5 Quick Launch satellites. It contained experiments for relaying signals from the United States Coast Guard Automatic Identification Sy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Equatorial Coordinate System
The equatorial coordinate system is a celestial coordinate system widely used to specify the positions of celestial objects. It may be implemented in spherical or rectangular coordinates, both defined by an origin at the centre of Earth, a fundamental plane consisting of the projection of Earth's equator onto the celestial sphere (forming the celestial equator), a primary direction towards the vernal equinox, and a right-handed convention. The origin at the centre of Earth means the coordinates are ''geocentric'', that is, as seen from the centre of Earth as if it were transparent. The fundamental plane and the primary direction mean that the coordinate system, while aligned with Earth's equator and pole, does not rotate with the Earth, but remains relatively fixed against the background stars. A right-handed convention means that coordinates increase northward from and eastward around the fundamental plane. Primary direction This description of the orientation of the r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Satellite Collision
Strictly speaking, a satellite collision is when two satellites collide while in orbit around a third, much larger body, such as a planet or moon. This definition can be loosely extended to include collisions between sub-orbital or escape-velocity objects with an object in orbit. Prime examples are the anti-satellite weapon tests. Natural-satellite collisions There have been no observed collisions between natural satellites of any Solar System planet or moon. Collision candidates for past events are: * Impact craters on many Jupiter (Jovian) and Saturn's (Saturnian) moons. They may have been formed by collisions with smaller moons, but they could equally likely have been formed by impacts with asteroids and comets during the Late Heavy Bombardment. * The far side of the Moon may have formed from the impact of a smaller moon that also formed during the giant impact event that created the Moon. * The objects making up the Rings of Saturn are believed to continually collide and aggr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Two-line Element Set
A two-line element set (TLE) is a data format encoding a list of orbital elements of an Earth-orbiting object for a given point in time, the ''epoch''. Using a suitable prediction formula, the state (position and velocity) at any point in the past or future can be estimated to some accuracy. The TLE data representation is specific to the simplified perturbations models (SGP, SGP4, SDP4, SGP8 and SDP8), so any algorithm using a TLE as a data source must implement one of the SGP models to correctly compute the state at a time of interest. TLEs can describe the trajectories only of Earth-orbiting objects. TLEs are widely used as input for projecting the future orbital tracks of space debris for purposes of characterizing "future debris events to support risk analysis, close approach analysis, collision avoidance maneuvering" and forensic analysis. The format was originally intended for punched cards, encoding a set of elements on two standard 80-column cards. This format was ev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Space Debris
Space debris (also known as space junk, space pollution, space waste, space trash, or space garbage) are defunct human-made objects in space—principally in Earth orbit—which no longer serve a useful function. These include derelict spacecraft—nonfunctional spacecraft and abandoned launch vehicle stages—mission-related debris, and particularly numerous in Earth orbit, fragmentation debris from the breakup of derelict rocket bodies and spacecraft. In addition to derelict human-made objects left in orbit, other examples of space debris include fragments from their disintegration, erosion and collisions or even paint flecks, solidified liquids expelled from spacecraft, and unburned particles from solid rocket motors. Space debris represents a risk to spacecraft. Space debris is typically a negative externality—it creates an external cost on others from the initial action to launch or use a spacecraft in near-Earth orbit—a cost that is typically not taken into account n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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