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 22,236 miles (35,785 km) 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.
Westar 1 was America's first domestic and commercially launched geostationary communications satellite, launched by Western Union (WU) and NASA on April 13, 1974. It was built by Hughes for Western Union, using the HS-333 platform of spin-stabilized satellites. It operated until May 1983.
Westar was a fleet of geosynchronous communications satellites operating in the C band which were launched by Western Union from 1974 to 1984. There were seven Westar satellites in all, with five of them launched and operating under the Westar name.
The PBS Satellite Service consists of feeds relayed from PBS by satellite to public television stations throughout the United States. The service was launched in September 1978. The service provides a mixed variety of programming selected from PBS's regular network services. In the X/XP years a satellite feed was multicast by some PBS member stations on an over-the-air DTV subchannel along with their regular programming, or during overnight hours on their main channel to provide a second opportunity for viewers to watch or record primetime programming.
SES World Skies was a short lived company formed as a result of the merger between the two SES subsidiaries, SES Americom and SES New Skies. The company was merged into its parent company, SES in 2011.
SES S.A., trading as SES is a Luxembourgish satellite telecommunications network provider supplying video and data connectivity worldwide to broadcasters, content and internet service providers, mobile and fixed network operators, governments and institutions.
SES Americom was a major commercial satellite operator of North American geosynchronous satellites based in the United States. The company started as RCA Americom in 1975 before being bought by General Electric in 1986 and then later acquired by SES in 2001. In September 2009, SES Americom and SES New Skies merged into SES World Skies.
Astra 1B was the second of the Astra communications satellites launched and operated by SES to add extra capacity to the satellite television services from 19.2° East, serving Germany, the United Kingdom and Ireland.
Galaxy 1 was the first in a line of Galaxy communications satellites launched by Hughes Communications in 1983.
Skypath is a system the NBC television network uses to distribute satellite programming to its affiliate stations.
AMC-18 is a geostationary Lockheed Martin A2100A communications satellite owned by SES Americom. It was launched on 8 December 2006 from Centre Spatial Guyanais aboard an Ariane 5 ECA launch vehicle and is situated at 83° West longitude, providing coverage of North America with twenty-four C-band transponders of 12–18 watts each. Future users in May 2007 include The CW Television Network, NASA TV and Canadian Broadcasting Corporation, among other services.
Satellite television is a service that delivers television programming to viewers by relaying it from a communications satellite orbiting the Earth directly to the viewer's location. The signals are received via an outdoor parabolic antenna commonly referred to as a satellite dish and a low-noise block downconverter.
AMC-11 , previously GE-11, is an American geostationary communications satellite which is operated by SES It is currently positioned in geostationary orbit at a longitude of 131° West, from where it is used to relay cable television across North America for onward distribution. It broadcasts to Canada, the Caribbean, Mexico and the United States.
AMC-4 is a commercial broadcast communications satellite owned by SES World Skies, part of SES. Launched in 1999, from Centre Spatial Guyanais, ELA-2 by Ariane 44LP H10-3. It provides coverage to North America, Latin America, Caribbean. Located in a geostationary orbit, AMC-4 provides service to commercial and government customers, with programming distribution, satellite news gathering and broadcast internet capabilities.
AMC-21, or GE-21, is an American communications satellite operated by SES S.A., formerly SES World Skies and SES Americom. It was launched in August 2008 and is expected to remain in service for approximately 15 years. It is currently located at 125° West longitude.
Astra 5A was one of the Astra communications satellites owned and operated by SES at the Astra 31.5°E. Launched in 1997 to the 5° East position by NSAB as Sirius 2, operation of the satellite was transferred to SES in April 2008 and the craft renamed and moved to 31.5° East to open up a new orbital position for the company for the development of markets in Central and Eastern Europe and the Middle East.
AMC-8, also known as Aurora III, previously GE-8, is a C-band satellite located at 139° West, covering the United States, Canada and the Caribbean. It is owned and operated by SES World Skies, formerly SES Americom and before that GE Americom. The satellite provides critical telecommunications services to AT&T Alascom, which occupies most of the satellite's capacity. AMC-8 was launched in 2000 as GE-8, and replaced Satcom-C5 in March 2001.
Currently, there are two primary satellite television providers of subscription based service available to United States consumers: DirecTV and Dish Network, which have 21 and 10 million subscribers respectively.
GE-2, called AMC-2 after 2001, is a privately owned American communications satellite launched in 1997. It was the first of the GE series to be launched outside the United States. It was launched by an Ariane 44L on 30 January 1997 at 22:04:00 UTC, flying from ELA-2, Centre Spatial Guyanais alongside another satellite, Nahuel 1A. It was owned by GE Americom until 2001 when the company was sold to SES. The name of the spacecraft was then changed by SES Americom to AMC-2 in 2001.
Intelsat K was a geostationary communication satellite built by Lockheed Martin. It was located at orbital position of 21.5 degrees west longitude and was owned by SES World Skies. The satellite was based on the AS-5000 platform and its life expectancy was 10 years. It was retired from service in August 2002 and transferred to a graveyard orbit.
