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Graveyard Orbit
A graveyard orbit, also called a junk orbit or disposal orbit, is an orbit that lies away from common operational orbits. One significant graveyard orbit is a supersynchronous orbit well beyond geosynchronous orbit. Some satellites are moved into such orbits at the end of their operational life to reduce the probability of colliding with operational spacecraft and generating space debris. Overview A graveyard orbit is used when the change in velocity required to perform a de-orbit maneuver is too large. De-orbiting a geostationary satellite requires a delta-v of about , whereas re-orbiting it to a graveyard orbit only requires about . For satellites in geostationary orbit and geosynchronous orbits, the graveyard orbit is a few hundred kilometers beyond the operational orbit. The transfer to a graveyard orbit beyond geostationary orbit requires the same amount of fuel as a satellite needs for about three months of stationkeeping. It also requires a reliable attitude control d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Animation Of Spaceway Around Earth - ECEF
Animation is a method by which still figures are manipulated to appear as moving images. In traditional animation, images are drawn or painted by hand on transparent celluloid sheets to be photographed and exhibited on film. Today, most animations are made with computer-generated imagery (CGI). Computer animation can be very detailed 3D animation, while 2D computer animation (which may have the look of traditional animation) can be used for stylistic reasons, low bandwidth, or faster real-time renderings. Other common animation methods apply a stop motion technique to two- and three-dimensional objects like paper cutouts, puppets, or clay figures. A cartoon is an animated film, usually a short film, featuring an exaggerated visual style. The style takes inspiration from comic strips, often featuring anthropomorphic animals, superheroes, or the adventures of human protagonists. Especially with animals that form a natural predator/prey relationship (e.g. cats and mice, coyo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Altitude
Altitude or height (also sometimes known as depth) is a distance measurement, usually in the vertical or "up" direction, between a reference datum and a point or object. The exact definition and reference datum varies according to the context (e.g., aviation, geometry, geographical survey, sport, or atmospheric pressure). Although the term ''altitude'' is commonly used to mean the height above sea level of a location, in geography the term elevation is often preferred for this usage. Vertical distance measurements in the "down" direction are commonly referred to as depth. In aviation In aviation, the term altitude can have several meanings, and is always qualified by explicitly adding a modifier (e.g. "true altitude"), or implicitly through the context of the communication. Parties exchanging altitude information must be clear which definition is being used. Aviation altitude is measured using either mean sea level (MSL) or local ground level (above ground level, or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
OneWeb
OneWeb (legally Network Access Associates Ltd) is a communications company that aims to build broadband satellite Internet services. The company is headquartered in London, and has offices in Virginia, US and a satellite manufacturing facility in FloridaOneWeb Satellitesthat is a joint venture with Airbus Defence and Space. The company was formerly known as WorldVu Satellites Ltd. The company was founded by Greg Wyler in 2012 and launched its first satellites in February 2019. It entered bankruptcy in March 2020 after failing to raise the requisite capital to complete the build and deployment of the remaining 90% of the network. The company emerged from the bankruptcy proceedings and reorganization in November 2020 with a new ownership group. As of 2021, Indian multinational company Bharti Global, France-based satellite service provider Eutelsat and the Government of the United Kingdom were the company's largest shareholders, while Japan's SoftBank retained an equity holding ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Delta-V
Delta-''v'' (more known as "change in velocity"), symbolized as ∆''v'' and pronounced ''delta-vee'', as used in spacecraft flight dynamics, is a measure of the impulse per unit of spacecraft mass that is needed to perform a maneuver such as launching from or landing on a planet or moon, or an in-space orbital maneuver. It is a scalar that has the units of speed. As used in this context, it is not the same as the physical change in velocity of the vehicle. As a simple example, take a conventional rocket-propelled spacecraft which achieves thrust by burning fuel. The spacecraft's delta-''v'' is the change in velocity that spacecraft can achieve by burning its entire fuel load. Delta-''v'' is produced by reaction engines, such as rocket engines, and is proportional to the thrust per unit mass and the burn time. It is used to determine the mass of propellant required for the given maneuver through the Tsiolkovsky rocket equation. For multiple maneuvers, delta-''v'' sums l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Artificial Satellites
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] |
Satellite Internet Constellation
A satellite internet constellation is a constellation of artificial satellites providing satellite internet service. In particular, the term has come to refer to a new generation of very large constellations (sometimes referred to as a megaconstellations ) orbiting in low Earth orbit (LEO) to provide low-latency, high bandwidth (broadband) internet service. History While more-limited satellite internet services have been available through geosynchronous commsats orbiting in geostationary orbit for years, these have been of quite limited bandwidth (not broadband), high- latency, and provided at such a relatively high price that demand for the services offered has been quite low. In the 1990s, several LEO satellite internet constellations were proposed and developed, including Celestri (63 satellites) and Teledesic (initially 840, later 288 satellites). These projects were abandoned after the bankruptcy of the Iridium and Globalstar satellite phone constellations in the ea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orbital Lifetime
Orbital may refer to: Sciences Chemistry and physics * Atomic orbital * Molecular orbital * Hybrid orbital Astronomy and space flight * Orbit ** Earth orbit Medicine and physiology * Orbit (anatomy), also known as the ''orbital bone'' * Orbitofrontal cortex, a part of the brain used for decision making Business * Orbital Corporation, an Australian engine technology company * Orbital Sciences Corporation, a U.S. satellite launch and defense systems corporation * Orbital ATK, American aerospace manufacturer formed from the merger of Orbital Sciences Corporation and parts of Alliant Techsystems Transportation * Ring road (or ''orbital road'' in some regions) * Orbital (metro), a rapid transit line usually encircling a city centre * Orbital engine Other uses * Orbital (The Culture), artificial worlds from Iain M. Banks's series of science fiction novels, the Culture * Orbital (band), an English electronic dance music duo ** ''Orbital'' (1991 album) ** ''Orbital'' (1993 album) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Astronautical Congress
Every year, the International Astronautical Federation with the support of the International Academy of Astronautics and the International Institute of Space Law (IISL), holds the International Astronautical Congress (IAC) which is hosted by one of the national society members of the IAF. They are an annual meeting of the actors in the discipline of space, and are generally held in late September or early October. They consist of plenary sessions, lectures and meetings. The IAC is attended by the agency heads and senior executives of the world's space agencies. As the Second World War came to an end, the United States and the Soviet Union held different and competing political worldviews. As the Cold War began to take shape, communication between the two countries became less frequent. Both countries turned their focus to achieving military superiority over the other. Six years after the Iron Curtain fell, the International Astronautical Federation (IAF) was formed by scient ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Passivation (spacecraft)
The passivation of a spacecraft is the removal of any internal energy contained in the vehicle at the end of its mission or useful life. Spent upper stages are generally passivated after their use as launch vehicles is complete, as are satellites when they can no longer be used for their design purpose. Internally stored energy generally takes the form of unused propellant and batteries. In the past, such stored energy has sometimes led to fragmentation or explosion, producing unwanted space debris. This was a fairly common outcome for many of the U.S. and Soviet rocket designs of the 1960s to the 1980s.A. Rossi et al"Effects of the RORSAT NaK Drops on the Long Term Evolution of the Space Debris Population" University of Pisa, 1997. It remains an occasional problem with derelict second stages left in higher Earth orbits; several U.S. rocket stages fragmented in 2018 and 2019. The International Telecommunication Union (ITU) and United Nations (UN) recommend that satellites in ge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Space
Space is the boundless three-dimensional extent in which objects and events have relative position and direction. In classical physics, physical space is often conceived in three linear dimensions, although modern physicists usually consider it, with time, to be part of a boundless four-dimensional continuum known as spacetime. The concept of space is considered to be of fundamental importance to an understanding of the physical universe. However, disagreement continues between philosophers over whether it is itself an entity, a relationship between entities, or part of a conceptual framework. Debates concerning the nature, essence and the mode of existence of space date back to antiquity; namely, to treatises like the ''Timaeus'' of Plato, or Socrates in his reflections on what the Greeks called ''khôra'' (i.e. "space"), or in the ''Physics'' of Aristotle (Book IV, Delta) in the definition of ''topos'' (i.e. place), or in the later "geometrical conception of place" as "spac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Federal Communications Commission
The Federal Communications Commission (FCC) is an independent agency of the United States federal government that regulates communications by radio, television, wire, satellite, and cable across the United States. The FCC maintains jurisdiction over the areas of broadband access, fair competition, radio frequency use, media responsibility, public safety, and homeland security. The FCC was formed by the Communications Act of 1934 to replace the radio regulation functions of the Federal Radio Commission. The FCC took over wire communication regulation from the Interstate Commerce Commission. The FCC's mandated jurisdiction covers the 50 states, the District of Columbia, and the territories of the United States. The FCC also provides varied degrees of cooperation, oversight, and leadership for similar communications bodies in other countries of North America. The FCC is funded entirely by regulatory fees. It has an estimated fiscal-2022 budget of US $388 million. It has 1,482 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telecommunication
Telecommunication is the transmission of information by various types of technologies over wire, radio, optical, or other electromagnetic systems. It has its origin in the desire of humans for communication over a distance greater than that feasible with the human voice, but with a similar scale of expediency; thus, slow systems (such as postal mail) are excluded from the field. The transmission media in telecommunication have evolved through numerous stages of technology, from beacons and other visual signals (such as smoke signals, semaphore telegraphs, signal flags, and optical heliographs), to electrical cable and electromagnetic radiation, including light. Such transmission paths are often divided into communication channels, which afford the advantages of multiplexing multiple concurrent communication sessions. ''Telecommunication'' is often used in its plural form. Other examples of pre-modern long-distance communication included audio messages, such as coded drumb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
