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Orion 3
Orion 3 was an American spacecraft which was intended for use by Orion Network Systems, as a geostationary communications satellite. It was to have been positioned in geostationary orbit at a longitude of 139° East, from where it was to have provided communications services to Asia and Oceania. Due to a malfunction during launch, it was instead delivered to a useless low Earth orbit. Orion 3 was constructed by Hughes Space and Communications, based on an HS-601HP satellite bus. It was equipped with 10 G/H band (IEEE C band) and 33 J band (IEEE Ku band) transponders, and at launch it had a mass of . The satellite was expected to remain operational for around fifteen years. Orion Network Systems merged with Loral Space & Communications in 1999 after the Orion 3 launch failure. Launch The Orion 3 satellite was launched on the second flight of the Delta III rocket, using the standard 8930 configuration. The launch occurred from Space Launch Complex 17B at the Cape Canaveral Ai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Communications Satellite
A communications satellite is an artificial satellite that relays and amplifies radio telecommunication signals via a transponder; it creates a communication channel between a source transmitter and a receiver at different locations on Earth. Communications satellites are used for television, telephone, radio, internet, and military applications. Many communications satellites are in geostationary orbit above the equator, so that the satellite appears stationary at the same point in the sky; therefore the satellite dish antennas of ground stations can be aimed permanently at that spot and do not have to move to track the satellite. Others form satellite constellations in low Earth orbit, where antennas on the ground have to follow the position of the satellites and switch between satellites frequently. The high frequency radio waves used for telecommunications links travel by line of sight and so are obstructed by the curve of the Earth. The purpose of communications sate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Satellite Bus
A satellite bus (or spacecraft bus) is the main body and structural component of a satellite or spacecraft, in which the payload and all scientific instruments are held. Bus-derived satellites are opposed to specially produced satellites. Bus-derived satellites are usually customized to customer requirements, for example with specialized sensors or transponders, in order to achieve a specific mission. They are commonly used for geosynchronous satellites, particularly communications satellites, but are also used in spacecraft which occupy lower orbits, occasionally including low Earth orbit missions. Examples Some satellite bus examples include: * Boeing DS&S 702 * Lockheed Martin Space Systems A2100 * Alphabus * INVAP ARSAT-3K * Airbus D&S Eurostar * ISRO's I-1K, I-2K, I-3K, I-4K, I-6K, and Indian Mini Satellite bus * NASA Ames MCSB * SSL 1300 * Orbital ATK GEOStar * Mitsubishi Electric DS2000 * Spacecraft bus of the James Webb Space Telescope * SPUTNIX TabletSat * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Space Shuttle
The Space Shuttle is a retired, partially reusable low Earth orbital spacecraft system operated from 1981 to 2011 by the U.S. National Aeronautics and Space Administration (NASA) as part of the Space Shuttle program. Its official program name was Space Transportation System (STS), taken from a 1969 plan for a system of reusable spacecraft where it was the only item funded for development. The first ( STS-1) of four orbital test flights occurred in 1981, leading to operational flights (STS-5) beginning in 1982. Five complete Space Shuttle orbiter vehicles were built and flown on a total of 135 missions from 1981 to 2011. They launched from the Kennedy Space Center (KSC) in Florida. Operational missions launched numerous satellites, interplanetary probes, and the Hubble Space Telescope (HST), conducted science experiments in orbit, participated in the Shuttle-''Mir'' program with Russia, and participated in construction and servicing of the International Space Station (ISS). ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NASA
The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. NASA was established in 1958, succeeding the National Advisory Committee for Aeronautics (NACA), to give the U.S. space development effort a distinctly civilian orientation, emphasizing peaceful applications in space science. NASA has since led most American space exploration, including Project Mercury, Project Gemini, the 1968-1972 Apollo Moon landing missions, the Skylab space station, and the Space Shuttle. NASA supports the International Space Station and oversees the development of the Orion spacecraft and the Space Launch System for the crewed lunar Artemis program, Commercial Crew spacecraft, and the planned Lunar Gateway space station. The agency is also responsible for the Launch Services Program, which provides oversight of launch operations and countdown management f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
US Dollar
The United States dollar (symbol: $; code: USD; also abbreviated US$ or U.S. Dollar, to distinguish it from other dollar-denominated currencies; referred to as the dollar, U.S. dollar, American dollar, or colloquially buck) is the official currency of the United States and several other countries. The Coinage Act of 1792 introduced the U.S. dollar at par with the Spanish silver dollar, divided it into 100 cents, and authorized the minting of coins denominated in dollars and cents. U.S. banknotes are issued in the form of Federal Reserve Notes, popularly called greenbacks due to their predominantly green color. The monetary policy of the United States is conducted by the Federal Reserve System, which acts as the nation's central bank. The U.S. dollar was originally defined under a bimetallic standard of (0.7735 troy ounces) fine silver or, from 1837, fine gold, or $20.67 per troy ounce. The Gold Standard Act of 1900 linked the dollar solely to gold. From 1934, its equi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Static Firing
Launch vehicle system tests assess the readiness of a launch system to safely reach orbit. Launch vehicles undergo system tests before they launch. A wet dress rehearsal (WDR) and a more extensive static fire tests a fully assembled launch vehicle and its associated ground support equipment (GSE) prior to launch. The spacecraft/payload may or may not be attached to the launch vehicle during the WDR or static fire, but sufficient elements of the rocket and all relevant ground support equipment are in place to help verify that the rocket is ready for flight. Propellant load tests and static fire tests may also be done on prototype rocket stages as well, in which case no fully assembled launch vehicle is involved. Wet dress rehearsal A wet dress rehearsal is called "wet" because the liquid propellant components (such as liquid oxygen, liquid hydrogen, etc.) are loaded into the rocket during the test. In a pure wet dress rehearsal the rocket engines are not ignited. Wet dress rehe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Combustion Chamber
A combustion chamber is part of an internal combustion engine in which the fuel/air mix is burned. For steam engines, the term has also been used for an extension of the firebox which is used to allow a more complete combustion process. Internal combustion engines In an internal combustion engine, the pressure caused by the burning air/fuel mixture applies direct force to part of the engine (e.g. for a piston engine, the force is applied to the top of the piston), which converts the gas pressure into mechanical energy (often in the form of a rotating output shaft). This contrasts an external combustion engine, where the combustion takes place in a separate part of the engine to where the gas pressure is converted into mechanical energy. Spark-ignition engines In spark ignition engines, such as petrol (gasoline) engines, the combustion chamber is usually located in the cylinder head. The engines are often designed such that the bottom of combustion chamber is roughly in li ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
USA-143
Milstar (Military Strategic and Tactical Relay) is a constellation of military communications satellites in geosynchronous orbit, which are operated by the United States Space Force, and provide secure and jam-resistant worldwide communications to meet the requirements of the Armed Forces of the United States. Six spacecraft were launched between 1994 and 2003, of which five are currently operational; the third launch failed, both damaging the satellite and leaving it in an unusable orbit. History Milstar Block I spacecraft, or Milstar Developmental Flight Satellite (DFS)-1 and -2, were designed with a Low Data Rate (LDR) payload in the wing of the satellite that broadcast in the Super High Frequency (SHF) and Extremely High Frequency (EHF) ranges, and also a classified communication payload in the wing. The DFS-1 satellite was launched on 7 February 1994 aboard the first Titan IV(401)A rocket, but with the classified wing payload deactivated. It was followed by the DFS-2 s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Titan IV
Titan IV was a family of heavy-lift space launch vehicles developed by Martin Marietta and operated by the United States Air Force from 1989 to 2005. Launches were conducted from Cape Canaveral Air Force Station, Florida and Vandenberg Air Force Base, California. The Titan IV was the last of the Titan family of rockets, originally developed by the Glenn L. Martin Company in 1958. It was retired in 2005 due to their high cost of operation and concerns over its toxic hypergolic propellants, and replaced with the Atlas V and Delta IV launch vehicles under the EELV program. The final launch (B-30) from Cape Canaveral occurred on 29 April 2005, and the final launch from Vandenberg AFB occurred on 19 October 2005. Lockheed Martin Space Systems built the Titan IVs near Denver, Colorado, under contract to the US government. Two Titan IV vehicles are currently on display at the National Museum of the United States Air Force in Dayton, Ohio and the Evergreen Aviation and Space Museu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Centaur (rocket Stage)
The Centaur is a family of rocket propelled upper stages produced by U.S. launch service provider United Launch Alliance, with one main active version and one version under development. The diameter Common Centaur/Centaur III flies as the upper stage of the Atlas V launch vehicle, and the diameter Centaur V is being developed as the upper stage of ULA's new Vulcan rocket. Centaur was the first rocket stage to use liquid hydrogen (LH2) and liquid oxygen (LOX) propellants, a high-energy combination that is ideal for upper stages but has significant handling difficulties. Characteristics Common Centaur is built around stainless steel pressure stabilized balloon propellant tanks with thick walls. It can lift payloads of up to . The thin walls minimize the mass of the tanks, maximizing the stage's overall performance. A common bulkhead separates the LOX and LH2 tanks, further reducing the tank mass. It is made of two stainless steel skins separated by a fiberglass honeycomb. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RL10
The RL10 is a liquid-fuel cryogenic rocket engine built in the United States by Aerojet Rocketdyne that burns cryogenic liquid hydrogen and liquid oxygen propellants. Modern versions produce up to of thrust per engine in vacuum. Three RL10 versions are in production for the Centaur upper stage of the Atlas V and the DCSS of the Delta IV. Three more versions are in development for the Exploration Upper Stage of the Space Launch System and the Centaur V of the Vulcan rocket. The expander cycle that the engine uses drives the turbopump with waste heat absorbed by the engine combustion chamber, throat, and nozzle. This, combined with the hydrogen fuel, leads to very high specific impulses (''I''sp) in the range of in a vacuum. Mass ranges from depending on the version of the engine. History The RL10 was the first liquid hydrogen rocket engine to be built in the United States, with development of the engine by Marshall Space Flight Center and Pratt & Whitney beginning in the 1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geosynchronous Transfer Orbit
A geosynchronous transfer orbit or geostationary transfer orbit (GTO) is a type of geocentric orbit. Satellites that are destined for geosynchronous (GSO) or geostationary orbit (GEO) are (almost) always put into a GTO as an intermediate step for reaching their final orbit. A GTO is highly elliptic. Its perigee (closest point to Earth) is typically as high as low Earth orbit (LEO), while its apogee (furthest point from Earth) is as high as geostationary (or equally, a geosynchronous) orbit. That makes it a Hohmann transfer orbit between LEO and GSO. Larson, Wiley J. and James R. Wertz, eds. Space Mission Design and Analysis, 2nd Edition. Published jointly by Microcosm, Inc. (Torrance, CA) and Kluwer Academic Publishers (Dordrecht/Boston/London). 1991. While some GEO satellites are launched direct to that orbit, often the launch vehicle lacks the power to put both the rocket and the satellite into that orbit. Instead extra fuel is added to the satellite, the launch vehicle la ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
