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Inmarsat-4 F3
Inmarsat-4 F3 is a communications I-4 satellite operated by the British satellite operator Inmarsat. It was launched into a geosynchronous orbit at 22:43 GMT on 18 August 2008, by a Proton-M/Briz-M Enhanced carrier rocket. It is currently located at 97.65° West longitude, providing coverage of the Americas. It entered service on 7 January 2009. Like the earlier Inmarsat-4 F1 and Inmarsat-4 F2, F2 satellites, Inmarsat-4 F3 was constructed by EADS Astrium, using a Eurostar E3000 satellite bus, bus. It has a mass of 5,960 kilograms, and is expected to operate for 13 years. It was originally slated for launch using an Atlas V 531, but was transferred to Proton due to a large backlog of Atlas launches. In the United States, Inmarsat ground stations are licensed to operate at 1525-1559 MHz and 1626.5-1660.5 MHz. The 1544-1545 MHz and 1645.5-1646.5 MHz bands are reserved for safety and distress communications. References External links *http://www.inmarsat.co ... [...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] |
Communications Satellites In Geostationary Orbit
Communication (from la, communicare, meaning "to share" or "to be in relation with") is usually defined as the transmission of information. The term may also refer to the message communicated through such transmissions or the field of inquiry studying them. There are many disagreements about its precise definition. John Peters argues that the difficulty of defining communication emerges from the fact that communication is both a universal phenomenon and a specific discipline of institutional academic study. One definitional strategy involves limiting what can be included in the category of communication (for example, requiring a "conscious intent" to persuade). By this logic, one possible definition of communication is the act of developing meaning among entities or groups through the use of sufficiently mutually understood signs, symbols, and semiotic conventions. An important distinction is between verbal communication, which happens through the use of a language, and non ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spacecraft Launched In 2008
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 res ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atlas V
Atlas V is an expendable launch system and the fifth major version in the Atlas (rocket family), Atlas launch vehicle family. It was originally designed by Lockheed Martin, now being operated by United Launch Alliance (ULA), a joint venture between Lockheed Martin and Boeing. Atlas V is also a major NASA launch vehicle. It is America's longest-serving active rocket. In August 2021, ULA announced that Atlas V would be retired, and all 29 remaining launches had been sold. , 19 launches remain. Each Atlas V launch vehicle consists of two main stages. The first stage (rocketry), first stage is powered by a Russian RD-180 engine manufactured by NPO Energomash, Energomash and burning kerosene and liquid oxygen. The Centaur (rocket stage), Centaur upper stage is powered by one or two American RL10 engine(s) manufactured by Aerojet Rocketdyne and burns liquid hydrogen and liquid oxygen. The Star 48 upper stage was used on the ''New Horizons'' mission as a third stage. strap-on booster, ... [...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] |
Inmarsat-4 F1
Inmarsat-4 F1 is a communications I-4 satellite operated by the British satellite operator Inmarsat. It was launched into a geosynchronous orbit at 21:42 GMT on 11 March 2005 from Space Launch Complex 41 at Cape Canaveral, Florida. By an Atlas V in the 431 configuration. It is currently located at 143.5 degrees East. Inmarsat-4 F1 was constructed by EADS Astrium, using a Eurostar E3000 The Eurostar E3000 is a generic satellite model most commonly used for commercial and military communications satellites manufactured by Airbus Defence and Space (formerly Astrium). It is a member of Airbus Defence and Space's Eurostar family. It ... bus. It has a mass of 5959 kg and is expected to operate for 13 years On 17 February 2018 Inmarsat-4 F1 experienced outage due to loss of attitude control. References {{reflist External links # http://space.skyrocket.de/doc_sdat/inmarsat-4.htm # http://www.inmarsat.com/about-us/our-satellites/our-coverage/ # http://www.as.northropgrumma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carrier Rocket
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] |
I-4 Satellite
Three I-4 satellites make up the INMARSAT BGAN, FleetBroadband and SwiftBroadband communications network. They provide Internet and telephony connections anywhere on Earth, except in polar regions. Data services Two general types of data service are currently provided: #Streaming #Background Streaming Streaming is a guaranteed delivery style of service. A terminal requests a context of X bandwidth (currently 8, 16, 32, 64, 128, or 256 kbit/s) and, if the current spot beam has enough resources available, it is allocated a guaranteed chunk of the available bandwidth. So if a request is made 8k streaming context, the terminal will, at all times, be able to send data at 8 kbit/s. As a result, streaming is billed based on time usage. Background Background is a best-effort style of service. Each spot beam provides a certain amount of usable bandwidth. The bandwidth which is not in use by Streaming contexts is used for Background contexts. This means that the actual amount of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eurostar E3000
The Eurostar E3000 is a generic satellite model most commonly used for commercial and military communications satellites manufactured by Airbus Defence and Space (formerly Astrium). It is a member of Airbus Defence and Space's Eurostar family. It utilises a chemical, bi-propellant propulsion system for orbit raising and on-station manoeuvres with an optional plasma propulsion system (PPS). The PPS harnesses the Newtonian effect as a result of the ionisation of xenon gas employed by the use of Hall effect plasma thrusters. This system is most commonly used for north–south station-keeping. The E3000 was the first commercial satellite family to use lithium–ion batteries rather than the older nickel-based technologies for power supply during eclipses. The E3000 bus can be modified extensively to meet customer requirements, but most of the E3000 satellites have a launch mass of between , and solar arrays between providing between nine and sixteen kilowatts at end of life. They te ... [...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] |
