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Astra 2D is one of the Astra communications satellites owned and operated by SES, and located at 28.2° east in the Clarke Belt till June 2015. It is a Hughes HS-376 craft, and was launched from the Guiana Space Centre in December 2000 to join Astra 2A and Astra 2B at 28.2°E, where it remained for its active life. As of February 2013, Astra 2D has carried no regularly active transponders.〔(Astra 2D at 28.2°E on lyngsat.com ) Accessed 15 February 2013〕 ==In service== While active, most of Astra 2D's transponders were used to provide television channels available on the Sky Digital satellite service to both Ireland and the United Kingdom, as well as the non-subscription service, Freesat. Provision of rights-sensitive broadcasts Free to air was made possible by the satellite's beam that was tightly focused on Ireland and the United Kingdom. However, surrounding countries had the ability to pick up the signal (dependent on suitably sized satellite dishes) and so could still access Freesat from outside the UK. Some channels on 2D were encrypted with Videoguard (a proprietary encryption method by the NDS Group) and only Sky Digiboxes with valid cards, or standard hardware with non-approved (with respect to the Sky/NDS end-user contract) "Dragon", or "T-Rex" conditional-access module can decode these channels. The BBC broadcast all of its domestic television channels (including BBC HD and the regional variations) from the Astra 2D satellite, except the BBC News Channel and BBC Parliament which broadcast from Astra 2A. All domestic BBC channels have been free to air since 29 July 2003. ITV also broadcast all its television channels (including regional variations of ITV1, and STV and UTV) from the Astra 2D satellite. All ITV channels have been free to air from 1 November 2005, although some regions reverted to Free-To-View encryption in 2008 when their lease on one 2D transponder could not be renewed. Channel 4 broadcast most of its channels free to air from this satellite, including Channel 4, Channel 4+1, E4, More4 and Film4 along with their timeshift variants. All were unencrypted apart from the feeds of Channel 4, Channel 4+1, E4 and E4+1 intended for viewers in Ireland, which remain encrypted. From November 2008, Five began to transmit free to air for the first time on Astra 2D, using borrowed space on a BBC transponder, allowing the channel to join Freesat. 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「Astra 2D」の詳細全文を読む スポンサード リンク
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