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Superbird-A2
Superbird-A2, known as Superbird-6 before launch, was a geostationary communications satellite ordered and operated by Space Communications Corporation (SCC) that was designed and manufactured by Hughes (now Boeing) on the BSS-601 satellite bus. It had a mixed Ku-band and Ka-band payload and was expected replace Superbird-A at the position at 158° East longitude. It was expected to provided television signals and business communications services throughout Japan, South Asia, East Asia, and Hawaii. While the launch was within the margins specified by the satellite manufacturer, the trajectory analysis had been inexact and the satellite suffered severe life and power degradation. It tried to use a supersynchronous transfer strategy, but Boeing had failed to take into consideration the effect of the Moon. Thus, the lowest part of the orbit dropped too fast and much propellant had to be spent on a fast transit to geosynchronous orbit. Additionally, the solar panels suffered dama ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Superbird-C2
Superbird-C2, known as Superbird-7 before launch, is a geostationary communications satellite operated by JSAT Corporation and designed and manufactured by Mitsubishi Electric on the DS2000 satellite bus. It had a launch weight of , a 15-year design life and was the first commercial communications satellite built in Japan. Its payload is composed of 28 Ku-band transponders with a total bandwidth of 828 MHz. It was originally ordered by Space Communications Corporation (SCC), but it was later merged and absorbed by JSAT Corporation. By the time of the actual launch it was a fully used Superbird-C2 as a replacement for Superbird-C to provide communications services to Japan, East Asia and the Pacific Ocean. History In April 2005, Space Communications Corporation (SCC) issued an Request for proposal (RFP) for Superbird-7, a spacecraft destined to replace the aging Superbird-C. On 28 June 2005, Mitsubishi Electric (MELCO) got first contract negotiations right, and on31 October ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Superbird-D
JCSAT-110, also known as N-SAT 110, JCSAT-7, Superbird-5 and Superbird-D, is a Japanese geostationary communications satellite which was operated by JSAT Corporation and Space Communications Corporation until both companies merged into SKY Perfect JSAT Group in 2008. It is positioned in geostationary orbit at a longitude of 110° East, from where it is used to provide communications services to Japan. Satellite description The spacecraft was designed and manufactured by Lockheed Martin on the A2100-AX satellite bus. It had a launch mass of with a dry mass of and a 13-year design life. As most satellites based on the A2100-AX platform, it uses a LEROS-1C liquid apogee engine (LAE) for orbit raising. When stowed for launch, the satellite was high. Its dual wing solar panels gave a power generation capability of 8.3 kW at the end of its design life, with a span of when deployed. With antennas deployed, its width was . Its payload is composed of twenty-four 36&nb ... [...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 communicat ... [...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 frequency ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Service Life
A product's service life is its period of use in service. Several related terms describe more precisely a product's life, from the point of manufacture, storage, and distribution, and eventual use. Service life has been defined as "a product's total life in use from the point of sale to the point of discard" and distinguished from replacement life, "the period after which the initial purchaser returns to the shop for a replacement". Determining a product's expected service life as part of business policy ( product life cycle management) involves using tools and calculations from maintainability and reliability analysis. Service life represents a commitment made by the item's manufacturer and is usually specified as a median. It is the time that any manufactured item can be expected to be "serviceable" or supported by its manufacturer. Service life is not to be confused with '' shelf life'', which deals with storage time, or with technical life, which is the maximum period d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Moon
The Moon is Earth's only natural satellite. It is the fifth largest satellite in the Solar System and the largest and most massive relative to its parent planet, with a diameter about one-quarter that of Earth (comparable to the width of Australia). The Moon is a planetary-mass object with a differentiated rocky body, making it a satellite planet under the geophysical definitions of the term and larger than all known dwarf planets of the Solar System. It lacks any significant atmosphere, hydrosphere, or magnetic field. Its surface gravity is about one-sixth of Earth's at , with Jupiter's moon Io being the only satellite in the Solar System known to have a higher surface gravity and density. The Moon orbits Earth at an average distance of , or about 30 times Earth's diameter. Its gravitational influence is the main driver of Earth's tides and very slowly lengthens Earth's day. The Moon's orbit around Earth has a sidereal period of 27.3 days. During each s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Supersynchronous Orbit
A supersynchronous orbit is either an orbit with a period greater than that of a synchronous orbit, or just an orbit whose apoapsis (apogee in the case of the Earth) is higher than that of a synchronous orbit. A synchronous orbit has a period equal to the rotational period of the body which contains the barycenter of the orbit. Geocentric supersynchronous orbits One particular supersynchronous orbital regime of significant economic value to Earth commerce is a band of near-circular Geocentric orbits beyond the geosynchronous belt—with perigee altitude above , approximately above synchronous altitude —called the geo graveyard belt. The geo graveyard belt orbital regime is valuable as a storage and disposal location for derelict satellite space debris after their useful economic life is completed as geosynchronous communication satellites. Artificial satellites are left in space because the economic cost of removing the debris would be high, and current public policy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Superbird-A
Superbird-A, also identified as Superbird-1 before launch, was a geostationary communications satellite designed and manufactured by Ford Aerospace) on the SSL 1300 satellite bus. It was originally ordered by Space Communications Corporation (SCC), which later merged into the SKY Perfect JSAT Group. It had a mixed Ku-band, Ka-band and X-band payload and operated on the 158° East longitude. It was ordered in 1985 along Superbird-B, Superbird-A1 and Superbird-B1 on the very first order of the SSL 1300 platform. It was also the first satellite of SCC and the second commercial satellite of Japan after JCSAT-1. It was used for video distribution, news gathering, remote publishing and high definition TV service to the main islands of Japan and Okinawa. Satellite description The spacecraft was the first satellite designed and manufactured by Ford Aerospace on the SSL 1300 satellite bus. It was based on the design of the Intelsat V series and offered a three-axis stabilized pl ... [...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 * SP ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hughes Space And Communications Company
Hughes may refer to: People * Hughes (surname) * Hughes (given name) Places Antarctica * Hughes Range (Antarctica), Ross Dependency * Mount Hughes, Oates Land * Hughes Basin, Oates Land * Hughes Bay, Graham Land * Hughes Bluff, Victoria Land * Hughes Glacier, Victoria Land * Hughes Island, Victoria Land * Hughes Peninsula, Ellsworth Land * Hughes Point, Ellsworth Land Australia * Division of Hughes, an electoral district * Hughes, Australian Capital Territory, a suburb of Canberra * Hughes, Northern Territory, a rural locality United States * Hughes, Alaska, a city * Hughes, Arkansas, a city * Hughes, Iowa, a ghost town * Hughes, Wisconsin, a town * Hughes County, Oklahoma * Hughes County, South Dakota * Hughes Lake (California) * Hughes Mountain, Missouri * Hughes River (Virginia) * Hughes River (West Virginia) Other * Hughes, Santa Fe, Argentina, a town * Hughes Range (British Columbia), Canada * Hughes Reef, South China Sea * 1878 Hughes, an asteroid B ... [...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 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 s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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