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Astra 1C
Astra 1C was a geostationary communications satellite launched in 1993 by the Société Européenne des Satellites ( SES), now SES Astra. The satellite remained in service until 2011 and is now derelict. History Astra 1C was the third communications satellite placed in orbit by SES, and was originally deployed at the Astra 19.2°E orbital position. The satellite was intended to be replaced in 2002, along with Astra 1B, by Astra 1K but this satellite failed to reach its intended orbit. It was eventually relieved of its remaining television/radio payloads by Astra 1KR in 2006. In November 2006, prior to the launch of Astra 1L to the 19.2° East position, Astra 1C was placed in an inclined orbit and moved first to 2.0° East for tests, and then in February 2007 to 4.6° East, notionally part of the Astra 5°E cluster of satellites but largely unused. After November 2008, the satellite operated back at 2.0° East, in an inclined orbit. On 2 November 2011, the satellite was ... [...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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
