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Ekspress ((ロシア語:Экспресс) meaning Express), is a series of geostationary communications satellites owned by Russian State Company for Satellite Communications. The first satellite of this kind was launched on October 13, 1994. The satellites are produced by the company JSC Information Satellite Systems. == Overview == The Ekspress series of communication satellites (industry code 11F639) was developed by the satellite company NPO PM as a replacement for the old Gorizont series of comsats. The first satellite of the series, Ekspress 1, was launched in 1994. It had a mass of 2.5 tons, 17 channels and an operational lifetime of at 5–7 years. Starting in the mid-1990s, NPO PM started to make significant effort to close the technology gap between Russian and Western communication satellites.〔 Cooperation with the French company Alcatel (now Thales Alenia Space) was begun in 1995. The first satellite of a new second series, Ekspress A-1, had 12 Alcatel-built transponders. It was lost in a rocket failure in 1999, but a replacement, Ekspress A-2 was successfully launched in March, 2000. A major improvement was the Ekspress AM version, first launched in 2003. It has an operational lifetime of 12–15 years and is able to carry 38 channels, including digital TV, radio, broadband and internet.〔 The launch of the Ekspress AM-3 spacecraft in June, 2005 completed the modernization of Russia's communications satellite network. Other versions of include the Ekspress 2000, which has a mass of 3.2 tonnes. It has up to 60 transponders, power of 25 kW and a lifetime of 15 years. Satellites using this platform are called the Ekspress AT series and the Ekspress AM30 and AM40 series. Ekspress 1000 is smaller than the 2000 version; 700 kg to 1,400 kg, 10 to 12 transponders, 2 kW of power and a lifetime of 15 years. Satellites based on Ekspress 1000 are called Ekspress AK or in its navigational version GLONASS K. The developer NPO PM later changed its name to JSC Information Satellite Systems. From 1999 to 2005, nine Ekspress-A and Ekspress-AM satellites were manufactured by the company.〔(【引用サイトリンク】title=Achievements in space activity )〕 On August 28, 2008 Ekspress-AM1 switched to DVB-S2 broadcasting system and became the first DVB-S2 satellite in CIS countries. The Ekspress-AM4 satellite was launched on August 17, 2011, but an anomaly with the Proton-M/Briz-M rocket left it in a useless orbit.〔(Second Life for Failed Russian Satellite? ) (23 March 2012)〕 The satellite was intentionally deorbited March 26, 2012, despite proposals to place the satellite into a higher-inclination orbit to provide coverage of the Antarctic. The Ekspress-MD2 satellite was lost in a similar failure in August 2012, when the Briz-M failed at the start of its third burn. 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「Ekspress」の詳細全文を読む スポンサード リンク
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