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AfriStar is a satellite family, operated by 1worldspace. The orbiting satellites and the satellite in storage were built by Alcatel Space and EADS Astrium, formerly known as Matra Marconi Space. Based on the Astrium's Eurostar E2000+ bus design, the geostationary orbit satellites broadcast digital radio programs in the L-Band frequency (1452-1492 MHz range). ==Satellites== Each of the satellites has three downlink spot beams, with each beam covering approximately 14 million square kilometers of the Earth. Plans to launch a third satellite, AmeriStar (a.k.a. CaribStar), to serve South America, Latin America, and the Caribbean from 95.0° west longitude were not carried out as the L-band frequencies used by 1worldspace are commandeered by the United States Air Force. This satellite was reconfigured and is now known as AfriStar 2. AfriStar 2 was to be launched to 21.0° east longitude in August 2007.〔()〕 This satellite, not yet launched as of the present, is intended to expand coverage for Western Europe in addition to the existing coverage of AfriStar 1, which it will eventually replace. 1worldspace will use ETSI Satellite Digital Radio (SDR) open standard in the new European coverage beam.〔() 〕 It is currently in storage at EADS Astrium’s and Thales Alenia Space facilities in Toulouse, France and Stevenage, U.K. A fourth satellite of identical design, for which long lead parts have been procured and partially assembled, is also maintained in storage in Toulouse, France and can be integrated and tested for launch in an abbreviated period of time. Each satellite has a design life of twelve years, with an orbital maneuver life of 15 years, which means that each satellite has been designed and fueled to maintain its assigned orbital position (within 0.1 degrees) for 15 years. After that point, the satellite must be decommissioned. The AfriStar satellite has developed a defect in its solar panels. As a result of this defect, the energy collected by those panels is less than intended. In March 2010, WorldStar announced that it was considering disposing of its satellites by boosting them to a higher orbit and expending their remaining fuel. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「AfriStar」の詳細全文を読む スポンサード リンク
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