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AsiaSat 3S
AsiaSat 3S, was a geosynchronous communications satellite for AsiaSat of Hong Kong to provide communications and television services all across Asia, the Middle East and Oceania Oceania (, , ) is a region, geographical region that includes Australasia, Melanesia, Micronesia, and Polynesia. Spanning the Eastern Hemisphere, Eastern and Western Hemisphere, Western hemispheres, Oceania is estimated to have a land area of .... Background In March 1998, AsiaSat ordered a replacement satellite, for US$195 million, from Hughes Space and Communications. Designated AsiaSat 3S, the new satellite is a replica of PAS-22, AsiaSat 3. Launch AsiaSat 3S was launched for AsiaSat by a Proton-K / Blok D, DM-2M launch vehicle on 21 March 1999, at 00:09:30 Coordinated Universal Time, UTC, destined for an orbital location at 105.5° East. A replacement for Asiasat 3, placed in the wrong orbit by a Proton launch in 1997, Asiasat 3S carried C band (IEEE), C-band and Ku band, Ku-band Transpon ... [...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] |
Middle East
The Middle East ( ar, الشرق الأوسط, ISO 233: ) is a geopolitical region commonly encompassing Arabian Peninsula, Arabia (including the Arabian Peninsula and Bahrain), Anatolia, Asia Minor (Asian part of Turkey except Hatay Province), East Thrace (European part of Turkey), Egypt, Iran, the Levant (including Syria (region), Ash-Shām and Cyprus), Mesopotamia (modern-day Iraq), and the Socotra Governorate, Socotra Archipelago (a part of Yemen). The term came into widespread usage as a replacement of the term Near East (as opposed to the Far East) beginning in the early 20th century. The term "Middle East" has led to some confusion over its changing definitions, and has been viewed by some to be discriminatory or too Eurocentrism, Eurocentric. The region includes the vast majority of the territories included in the closely associated definition of Western Asia (including Iran), but without the South Caucasus, and additionally includes all of Egypt (not just the Sina ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AsiaSat 7
AsiaSat 7 is a Hong Kong communications satellite, which is operated by the Hong Kong based Asia Satellite Telecommunications Company (AsiaSat). It is positioned in geostationary orbit at a longitude of 105° East of the Greenwich Meridian, where it serves as a back-up for the AsiaSat 5 satellite and replaced AsiaSat 3S. It is used to provide fixed satellite services, including broadcasting, telephone and broadband very small aperture terminal (VSAT) communications, to Asia and the Pacific Ocean region. Satellite description Space Systems/Loral and AsiaSat announced in May 2009, that it has been chosen to provide a new communications satellite, named AsiaSat 5C. In early 2010, the satellite was renamed AsiaSat 7. At launch, AsiaSat 7 had a mass of , and was expected to operate for fifteen years. It carries 26 C-band and 14 Ku-band transponders. Launch AsiaSat 7 was built by Space Systems/Loral, and is based on the LS-1300 satellite bus. It is being launched by Interna ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AsiaSat 1
AsiaSat 1 was a Hong Kong communications satellite, which was owned, and was operated, by the Hong Kong based Asia Satellite Telecommunications Company. It was positioned in geostationary orbit at a longitude of 100.5° East. It spent its operational life at 100.5° East, from where it was used to provide fixed satellite services, including broadcasting, audio and data transmission, to Asia and the Pacific Ocean. Satellite description AsiaSat 1 was built by Hughes Space and Communications. It is based on the HS-376 satellite bus. At launch, it had a mass of , and a design life of thirteen years. It carries twenty four C-band transponders. Launch The launch of AsiaSat 1 was contracted to the China Great Wall Industry Corporation (CGWIC), and used a Long March 3 launch vehicle. The launch was conducted from Xichang Launch Area 3 (LA-3) at the Xichang Satellite Launch Centre at 13:30:02 UTC on 7 April 1990. Westar 6 Westar 6 was launched from the space shuttle in Februa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apsis
An apsis (; ) is the farthest or nearest point in the orbit of a planetary body about its primary body. For example, the apsides of the Earth are called the aphelion and perihelion. General description There are two apsides in any elliptic orbit. The name for each apsis is created from the prefixes ''ap-'', ''apo-'' (), or ''peri-'' (), each referring to the farthest and closest point to the primary body the affixing necessary suffix that describes the primary body in the orbit. In this case, the suffix for Earth is ''-gee'', so the apsides' names are ''apogee'' and ''perigee''. For the Sun, its suffix is ''-helion'', so the names are ''aphelion'' and ''perihelion''. According to Newton's laws of motion, all periodic orbits are ellipses. The barycenter of the two bodies may lie well within the bigger body—e.g., the Earth–Moon barycenter is about 75% of the way from Earth's center to its surface. If, compared to the larger mass, the smaller mass is negligible (e.g., f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apogee Kick Motor
An apogee kick motor (AKM) is a rocket motor 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 accordan ... that is regularly employed on artificial satellites to provide the final impulse to change the trajectory from the transfer orbit into its final (most commonly circular) orbit. For a satellite launched from the Earth, the rocket firing is done at the highest point of the transfer orbit, known as the apsis, apogee. An apogee kick motor is used, for example, for satellites launched into a geostationary orbit. As the vast majority of geostationary satellite launches are carried out from spaceports at a significant distance away from Earth's equator, the carrier rocket often only launches the satellite into an orbit with a non-zero inclination approximately equal to the latitude of the l ... [...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] |
PAS-22
AsiaSat 3, previously known as HGS-1 and then PAS-22, was a geosynchronous communications satellite, which was salvaged from an unusable geosynchronous transfer orbit (GTO) by means of the Moon's gravity. Launch of AsiaSat 3 AsiaSat 3 was launched for AsiaSat of Hong Kong to provide communications and television services in Asia by a Proton-K / DM-2M launch vehicle on 24 December 1997, destined for an orbital position at 105.5° East. However, a failure of the Blok DM-2M fourth stage left it stranded in a highly inclined (51.6°) and elliptical orbit, although still fully functional. It was declared a total loss by its insurers. HGS-1 The satellite was transferred to Hughes Global Services Inc., which was then a subsidiary of Hughes Space and Communications, with an agreement to share any profits with the consortium of 27 insurers. Edward Belbruno and Rex Ridenoure heard about the problem and proposed a 3–5 month low-energy transfer trajectory that would swing past t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hong Kong
Hong Kong ( (US) or (UK); , ), officially the Hong Kong Special Administrative Region of the People's Republic of China ( abbr. Hong Kong SAR or HKSAR), is a city and special administrative region of China on the eastern Pearl River Delta in South China. With 7.5 million residents of various nationalities in a territory, Hong Kong is one of the most densely populated places in the world. Hong Kong is also a major global financial centre and one of the most developed cities in the world. Hong Kong was established as a colony of the British Empire after the Qing Empire ceded Hong Kong Island from Xin'an County at the end of the First Opium War in 1841 then again in 1842.. The colony expanded to the Kowloon Peninsula in 1860 after the Second Opium War and was further extended when Britain obtained a 99-year lease of the New Territories in 1898... British Hong Kong was occupied by Imperial Japan from 1941 to 1945 during World War II; British administration resume ... [...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] |
Geosynchronous
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. Communi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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