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Optus D3
Optus D3 is an Australian geostationary communications satellite, which is operated by Optus and provides communications services to Australasia. D3 was the third Optus-D satellite to be launched. It is a satellite, which was constructed by Orbital Sciences Corporation based on the Star-2.4 satellite bus, with the same configuration as the earlier Optus D2 satellite. It was launched, along with the Japanese JCSAT-12 satellite, by Arianespace. An Ariane 5ECA rocket was used for the launch, which occurred from ELA-3 at the Guiana Space Centre in Kourou, French Guiana. The launch took place at 22:09 GMT on 21 August 2009, at the start of a 60-minute launch window. Optus D3 separated from its carrier rocket into a geosynchronous transfer orbit, from which it raised itself to geostationary orbit using an IHI -500-N apogee motor. It has a design life of fifteen years, and carries thirty two J band transponders (US IEEE Ku band). See also *2009 in spaceflight Several signifi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Optus Fleet Of Satellites
This is a list of the satellites operated by Optus, an Australian telecommunications company. The satellite communications facility is located at Belrose on Sydney's Northern Beaches. Optus' satellites are divided into 4 classes A, B, C and D. As of April 2014 it owns and operates Optus B3, Optus C1, Optus D1, Optus D2 and Optus D3. Optus A1, Optus A2, Optus A3 and Optus B1 satellites have been retired. Optus has the largest network of satellites in Australia and New Zealand. On February 2, 2014 NBN Co of Australia chose Optus for a five-year contract to operate two purpose-built satellites (the Sky Muster satellites) to deliver high speed broadband across rural and remote Australia. A-Class *Satellite Type: Hughes HS-376 *Design Life: 7 Years for A1 & A2 - 10 Years for A3 *Equipment: 15 Ku band transponders (including four 30W transponders and eleven 12W transponders) *Diameter: 2.2m *Height: 2.9m (stowed), 6.3m (deployed) The Aussat A-Class satellites were funded by the Gover ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Optus D2
This is a list of the satellites operated by Optus, an Australian telecommunications company. The satellite communications facility is located at Belrose on Sydney's Northern Beaches. Optus' satellites are divided into 4 classes A, B, C and D. As of April 2014 it owns and operates Optus B3, Optus C1, Optus D1, Optus D2 and Optus D3. Optus A1, Optus A2, Optus A3 and Optus B1 satellites have been retired. Optus has the largest network of satellites in Australia and New Zealand. On February 2, 2014 NBN Co of Australia chose Optus for a five-year contract to operate two purpose-built satellites (the Sky Muster satellites) to deliver high speed broadband across rural and remote Australia. A-Class *Satellite Type: Hughes HS-376 *Design Life: 7 Years for A1 & A2 - 10 Years for A3 *Equipment: 15 Ku band transponders (including four 30W transponders and eleven 12W transponders) *Diameter: 2.2m *Height: 2.9m (stowed), 6.3m (deployed) The Aussat A-Class satellites were funded by the Gover ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
JCSAT-12
JCSAT-RA, previously known as JCSAT-12, is a Japanese geostationary communications satellite, which is operated by SKY Perfect JSAT Group. Details It was ordered to replace the JCSAT-11 satellite which was lost in a launch failure on a Proton-M/Briz-M rocket in 2007, and is currently used as an on-orbit spare satellite; a role in which it replaced the older JCSAT-R spacecraft, providing a reserve for if one of the company's other satellites fails. It is a satellite, which was constructed by Lockheed Martin based on the A2100AX satellite bus, with the same configuration as JCSAT-10 and JCSAT-11. The contract to build JCSAT-12 was awarded on 6 September 2007, the day after JCSAT-11 failed to reach orbit. It was launched, along with the Australian Optus D3 satellite, by Arianespace. An Ariane 5ECA rocket was used for the launch, which occurred from ELA-3 at the Guiana Space Centre in Kourou, French Guiana. The launch took place at 22:09 GMT on 21 August 2009, at the start of a 60- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Satellites Of Australia
A satellite or artificial satellite is an object intentionally placed into orbit in outer space. Except for passive satellites, most satellites have an electricity generation system for equipment on board, such as solar panels or radioisotope thermoelectric generators (RTGs). Most satellites also have a method of communication to ground stations, called transponders. Many satellites use a standardized bus to save cost and work, the most popular of which is small CubeSats. Similar satellites can work together as a group, forming constellations. Because of the high launch cost to space, satellites are designed to be as lightweight and robust as possible. Most communication satellites are radio relay stations in orbit and carry dozens of transponders, each with a bandwidth of tens of megahertz. Satellites are placed from the surface to orbit by launch vehicles, high enough to avoid orbital decay by the atmosphere. Satellites can then change or maintain the orbit by propulsion, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Communications Satellite Constellations
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2009 In Spaceflight
Several significant events in spaceflight occurred in 2009, including Iran conducting its first indigenous orbital launch, the first Swiss satellite being launched and New Zealand launching its first sounding rocket. The H-IIB and Naro-1 rockets conducted maiden flights, whilst the Tsyklon-3, Falcon 1 and Ariane 5GS were retired from service. The permanent crew of the International Space Station increased from three to six in May, and in the last few months of the year, Japan's first resupply mission to the outpost, HTV-1, was conducted successfully. Overview The internationally accepted definition of a spaceflight is any flight which crosses the Kármán line, 100 kilometres above sea level. The first spaceflight launch of the year was that of a Delta IV Heavy, carrying the USA-202 ELINT satellite, which launched from Cape Canaveral Air Force Station at 02:47 GMT on 18 January. This was also the first orbital launch of the year. On 2 February, Iran conducted its first s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transponder
In telecommunications, a transponder is a device that, upon receiving a signal, emits a different signal in response. The term is a blend word, blend of ''transmitter'' and ''responder''. In air navigation or radio frequency identification, a Transponder (aeronautics), flight transponder is an automated transceiver in an aircraft that emits a coded identifying signal in response to an interrogating received signal. In a communications satellite, a Transponder (satellite communications), satellite transponder receives signals over a range of uplink frequencies, usually from a satellite ground station; the transponder amplifies them, and re-transmits them on a different set of downlink frequencies to receivers on Earth, often without changing the content of the received signal or signals. Satellite/broadcast communications A communications satellite’s Communication channel, channels are called transponders because each is a separate transceiver or repeater. With digital video d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apogee Motor
An apogee kick motor (AKM) is a rocket motor 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 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 launch site. This orbit is commonly known as a "geostationary transfer orbit" or a "geosynchronous transfer orbit". The satellite must then provide thrust to bring forth the needed delta v to reach a geostationary orbit. This is typically done with a fixed onboa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IHI -500-N
Ihi, Ehee (Nepal Bhasa:ईही) is a ceremony in the Newar community in Nepal in which pre-adolescent girls are "married" to the Suvarna Kumar which is a symbol of the god Vishnu, ensuring that the girl becomes and remains fertile. It is believed that if the girl's husband dies later in her life, she is not considered a widow because she is married to Vishnu, and so already has a husband that is believed to be still alive. This was basically done to dodge the tradition of 'Sati Pratha', where after the husband dies, the widow sacrifices herself in the burning fire. Ihi is falsely labeled as "Bel Bibaha". However, this naming is incorrect as "Bel Bibaha" would mean marriage to a fruit Bel(or Bael). At the core of the Ihi is a traditional Hindu ceremony of marriage, but the spouse is Visnu/Narayana. This ritual has been in practice for hundreds of years. It is a highly sacred ritual and a real kanyaadaan as a virgin girl is handed over to God. Actually, during the Ihi ceremony ... [...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] |
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] |
Launch Window
In the context of spaceflight, launch period is the collection of days and launch window is the time period on a given day during which a particular rocket must be launched in order to reach its intended target. If the rocket is not launched within a given window, it has to wait for the window on the next day of the period. Launch periods and launch windows are very dependent on both the rocket's capability and the orbit to which it is going. A launch period refers to the days that the rocket can launch to reach its intended orbit. A mission could have a period of 365 days in a year, a few weeks each month, a few weeks every 26 months (e.g. Mars launch periods), or a short period time that won't be repeated. A launch window indicates the time frame on a given day in the launch period that the rocket can launch to reach its intended orbit. This can be as short as a second (referred to as an instantaneous window) or even the entire day. For operational reasons, the window almost ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
