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USA-243
USA-243, also known as WGS-5, is a United States military communications satellite. It was the fifth satellite to be launched as part of the Wideband Global SATCOM program, and the second Block II satellite. Overview The WGS system is a constellation of military communications satellites that use cost-effective methods and technological advances in the communications satellite industry. The WGS system is composed of three principal segments: Space Segment (satellites), Control Segment (operators), and Terminal Segment (users). Each WGS satellite provides service in multiple frequency bands, with the ability to cross-band between the two frequencies on board the satellite. WGS augments other satellites. In early 2001, a satellite communications industry team led by Boeing Satellite Systems was selected to develop the Wideband Gapfiller Satellite (WGS) system as a successor to the Defense Satellite Communications System (DSCS) series of communications satellites. It is intende ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
USA-244
USA-244, or Wideband Global SATCOM 6 (WGS-6) is a United States military communications satellite operated by the United States Air Force as part of the Wideband Global SATCOM programme. Launched in 2013, it was the sixth WGS satellite to reach orbit. It is stationed at a longitude of 135° West, in geostationary orbit. WGS-6 was procured by the Australian Defence Force for the U.S. Air Force, in exchange for participation in the programme. Overview The WGS system is a constellation of highly capable military communications satellites that leverage cost-effective methods and technological advances in the communications satellite industry. The WGS system is composed of three principal segments: Space Segment (satellites), Control Segment (operators) and Terminal Segment (users). Each WGS satellite provides service in multiple frequency bands, with the unprecedented ability to cross-band between the two frequencies on board the satellite. WGS augments other satellites. In ear ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wideband Global SATCOM
The Wideband Global SATCOM system (WGS) is a high capacity United States Space Force satellite communications system planned for use in partnership by the United States Department of Defense (DoD), Canadian Department of National Defence (DND) and the Australian Department of Defence. The system is composed of the ''Space Segment'' satellites, the ''Terminal Segment'' users and the ''Control Segment'' operators. DoD wideband satellite communication services are currently provided by a combination of the existing Defense Satellite Communications System (DSCS) and Global Broadcast Service (GBS) satellites. According to United Launch Alliance, quoted on ''Spaceflight Now'', "A single WGS spacecraft has as much bandwidth as the entire existing DSCS constellation." WGS operations are currently run by the 4th Space Operations Squadron, out of Schriever Space Force Base, as well as the 53rd Space Operations Squadron. Mission The constellation of WGS satellites increases the commun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
USA-233
USA-233, or Wideband Global SATCOM 4 (WGS-4) is a United States military communications satellite operated by the United States Air Force as part of the Wideband Global SATCOM program, launched in 2012. The fourth Wideband Global SATCOM satellite, it is the first WGS Block II satellite to be launched. It is stationed at 88.5° East (Indian Ocean) in geostationary orbit. Overview The Wideband Gapfiller SATCOM (WGS) system is a constellation of military communications satellites. The WGS system is composed of three principal segments: Space Segment (satellites), Control Segment (operators) and Terminal Segment (users). Each WGS satellite provides service in multiple frequency bands, with the ability to cross-band between the two frequencies on board the satellite. In early 2001, a satellite communications industry team led by Boeing Satellite Systems was selected to develop the WGS system as successors to the Defense Satellite Communications System (DSCS) series of communica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
USA Satellites
This is a list of satellites and spacecraft which have been given USA designations by the United States Air Force. These designations have been applied to most United States military satellites since 1984, and replaced the earlier OPS designation. As of June 2022, USA designations have been assigned to 331 space satellites. There is not always a one-to-one mapping between launch vehicles and mission spacecraft. This can occasionally result in gaps when maintaining records that incorrectly make that assumption, such as the "missing" entries for USA-163 (which are, symmetrically, contemporary with confusion over "splitting" spacecraft tracks). List See also * List of NRO launches References External links Directory of U.S. Military Rockets and Missiles - Satellite Launch ListEncyclopedia Astronautica {{Space exploration lists and timelines USA The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a cou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hertz
The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), equivalent to one event (or cycle) per second. The hertz is an SI derived unit whose expression in terms of SI base units is s−1, meaning that one hertz is the reciprocal of one second. It is named after Heinrich Rudolf Hertz (1857–1894), the first person to provide conclusive proof of the existence of electromagnetic waves. Hertz are commonly expressed in multiples: kilohertz (kHz), megahertz (MHz), gigahertz (GHz), terahertz (THz). Some of the unit's most common uses are in the description of periodic waveforms and musical tones, particularly those used in radio- and audio-related applications. It is also used to describe the clock speeds at which computers and other electronics are driven. The units are sometimes also used as a representation of the energy of a photon, via the Planck relation ''E'' = ''hν'', where ''E'' is the photon's energy, ''ν'' is its freq ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spacecraft Launched In 2013
A spacecraft is a vehicle or machine designed to fly in outer space. A type of artificial satellite, spacecraft are used for a variety of purposes, including communications, Earth observation, meteorology, navigation, space colonization, planetary exploration, and transportation of humans and cargo. All spacecraft except single-stage-to-orbit vehicles cannot get into space on their own, and require a launch vehicle (carrier rocket). On a sub-orbital spaceflight, a space vehicle enters space and then returns to the surface without having gained sufficient energy or velocity to make a full Earth orbit. For orbital spaceflights, spacecraft enter closed orbits around the Earth or around other celestial bodies. Spacecraft used for human spaceflight carry people on board as crew or passengers from start or on orbit (space stations) only, whereas those used for robotic space missions operate either autonomously or telerobotically. Robotic spacecraft used to support scientific re ... [...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] |
Geostationary Transfer Orbit
A geosynchronous transfer orbit or geostationary transfer orbit (GTO) is a type of geocentric orbit. Satellite, Satellites that are destined for geosynchronous orbit, 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 orbit, 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 geostationary orbit, 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. I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Launch Vehicle
A launch vehicle or carrier rocket is a rocket designed to carry a payload (spacecraft or satellites) from the Earth's surface to outer space. Most launch vehicles operate from a launch pad, launch pads, supported by a missile launch control center, launch control center and systems such as vehicle assembly and fueling. Launch vehicles are engineered with advanced aerodynamics and technologies, which contribute to large operating costs. An orbital spaceflight, orbital launch vehicle must lift its payload at least to the boundary of space, approximately and accelerate it to a horizontal velocity of at least . Suborbital spaceflight, Suborbital vehicles launch their payloads to lower velocity or are launched at elevation angles greater than horizontal. Practical orbital launch vehicles are multistage rockets which use chemical propellants such as Solid-propellant rocket, solid fuel, liquid hydrogen, kerosene, liquid oxygen, or Hypergolic propellants. Launch vehicles are cla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ion Engine
An ion thruster, ion drive, or ion engine is a form of electric propulsion used for spacecraft propulsion. It creates thrust by accelerating ions using electricity. An ion thruster ionizes a neutral gas by extracting some electrons out of atoms, creating a cloud of positive ions. Ion thrusters are categorized as either electrostatic or electromagnetic. Electrostatic thruster ions are accelerated by the Coulomb force along the electric field direction. Temporarily stored electrons are reinjected by a ''neutralizer'' in the cloud of ions after it has passed through the electrostatic grid, so the gas becomes neutral again and can freely disperse in space without any further electrical interaction with the thruster. By contrast, electromagnetic thruster ions are accelerated by the Lorentz force to accelerate all species (free electrons as well as positive and negative ions) in the same direction whatever their electric charge, and are specifically referred to as plasma propu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rocket Engine
A rocket engine uses stored rocket propellants as the reaction mass for forming a high-speed propulsive jet of fluid, usually high-temperature gas. Rocket engines are reaction engines, producing thrust by ejecting mass rearward, in accordance with Newton's third law. Most rocket engines use the combustion of reactive chemicals to supply the necessary energy, but non-combusting forms such as cold gas thrusters and nuclear thermal rockets also exist. Vehicles propelled by rocket engines are commonly called rockets. Rocket vehicles carry their own oxidiser, unlike most combustion engines, so rocket engines can be used in a vacuum to propel spacecraft and ballistic missiles. Compared to other types of jet engine, rocket engines are the lightest and have the highest thrust, but are the least propellant-efficient (they have the lowest specific impulse). The ideal exhaust is hydrogen, the lightest of all elements, but chemical rockets produce a mix of heavier species, reducing the e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
