1. geostationary satellite

2. Communications satellite History
An immediate antecedent of the geostationary satellites was Hughes' Syncom 2, launched on July 26, Syncom 2 revolved around the earth once per day at constant speed, but because it still had north-south motion, special equipment was needed to track it.

3. Communications satellite Geostationary orbits
The first geostationary satellite was Syncom 3, launched on August 19, 1964, and used for communication across the Pacific starting with television coverage of the 1964 Summer Olympics. Shortly after Syncom 3, Intelsat I, aka Early Bird, was launched on April 6, 1965 and placed in orbit at 28° west longitude. It was the first geostationary satellite for telecommunications over the Atlantic Ocean.

4. Communications satellite Geostationary orbits
On November 9, 1972, Canada's first geostationary satellite serving the continent, Anik A1, was launched by Telesat Canada, with the United States following suit with the launch of Westar 1 by Western Union on April 13, 1974.

5. Communications satellite Low-Earth-orbiting satellites
Low-Earth-orbiting satellites are less expensive to launch into orbit than geostationary satellites and, due to proximity to the ground, do not require as high signal strength (Recall that signal strength falls off as the square of the distance from the source, so the effect is dramatic). Thus there is a trade off between the number of satellites and their cost. In addition, there are important differences in the onboard and ground equipment needed to support the two types of missions.

6. Communications satellite Molniya satellites
For areas close to the North (and South) Pole, a geostationary satellite may appear below the horizon

7. Communications satellite Telephone
The fixed Public Switched Telephone Network relays telephone calls from land line telephones to an earth station, where they are then transmitted to a geostationary satellite

8. Satellite - Early conceptions
The book described geostationary satellites (first put forward by Tsiolkovsky) and discussed communication between them and the ground using radio, but fell short of the idea of using satellites for mass broadcasting and as telecommunications relays.

9. Satellite - Early conceptions
In a 1945 Wireless World article the English science fiction writer Arthur C. Clarke (1917–2008) described in detail the possible use of communications satellites for mass communications. Clarke examined the logistics of satellite launch, possible orbits and other aspects of the creation of a network of world-circling satellites, pointing to the benefits of high-speed global communications. He also suggested that three geostationary satellites would provide coverage over the entire planet.

10. Satellite - End of life
As of 2002, the FCC requires all geostationary satellites to commit to moving to a graveyard orbit at the end of their operational life prior to launch

11. Satellite - Jamming
Also, it is trivial to transmit a carrier radio signal to a geostationary satellite and thus interfere with the legitimate uses of the satellite's transponder

12. Satellite Internet access
Satellite Internet access is Internet access provided through communications satellites. Modern satellite Internet service is typically provided to users through geostationary satellites that can offer high data speeds, with newer satellites achieving downstream data speeds up to 15 Mbps

13. Satellite Internet access - History of satellite Internet
Following the invention of the Internet and the World Wide Web, geostationary satellites attracted interest as a potential means of providing Internet access.

14. Satellite Internet access - Signal latency
The round trip latency of a geostationary satellite communication's network is almost 20 times that of a terrestrial based network.

15. Satellite Internet access - Geostationary unsuitable for low-latency applications
Compared to ground-based communication, all geostationary satellite communications experience high latency due to the signal having to travel 35,786 km (22,236 mi) to a satellite in geostationary orbit and back to Earth again

16. Satellite Internet access - Geostationary unsuitable for low-latency applications
For geostationary satellites, there is no way to eliminate latency, but the problem can be somewhat mitigated in Internet communications with TCP acceleration features that shorten the round trip time (RTT) per packet by splitting the feedback loop between the sender and the receiver. Such acceleration features are usually present in recent technology developments embedded in new satellite Internet services.

17. Satellite Internet access - Acceptable latencies, but lower speeds, of lower orbits
Unlike geostationary satellites, low and medium Earth orbit satellites do not stay in a fixed position in the sky

18. Satellite Internet access - System components
Latency is still high, although lower than full two-way geostationary satellite Internet, since only half of the data path is via satellite, the other half being via the terrestrial channel.

19. Telecommunication - Satellite
The fixed Public Switched Telephone Network relays telephone calls from land line telephones to an earth station, where they are then transmitted to a receiving satellite dish via a geostationary satellite in Earth orbit

20. Telecommunications in Brazil - Satellite connections
List of business and satellites they operate (Brazilian Geostationary Satellites)

21. History of telecommunication - Satellite
The fixed Public Switched Telephone Network relays telephone calls from land line telephones to an earth station, where they are then transmitted a receiving satellite dish via a geostationary satellite in Earth orbit

22. Telenor - Broadcast
Telenor also operates the national terrestrial broadcast network in Norway, through its subsidiary Norkring. It is also part owner of Norges Televisjon and the content provider RiksTV. Telenor is also the leading provider of satellite broadcasting services in the Nordic region, utilising three geostationary satellites. Telenor's key objective is to further strengthen Broadcast's position in the Nordic region.

23. Voice over IP - Quality of service
Fixed delays cannot be controlled as they are caused by the physical distance the packets travel. They are especially problematic when satellite circuits are involved because of the long distance to a geostationary satellite and back; delays of 400–600 ms are typical.

24. Space elevator - 20th century
Artsutanov suggested using a geostationary satellite as the base from which to deploy the structure downward

25. Satellite Internet access - Acceptable latencies, but lower speeds, of lower orbits
Unlike geostationary satellites, low and medium Earth orbit satellites do not stay in a fixed position in the sky

26. Telecommunications in the Cook Islands - Internet
It has a latency (engineering)|latency of about 100 milliseconds because it is much closer to Earth than standard geostationary satellites, whose latencies can be over 600 milliseconds

27. Telecommunications in North America - Satellite
The fixed Public Switched Telephone Network relays telephone calls from land line telephones to an earth station, where they are then transmitted to a receiving satellite dish via a geostationary satellite in Earth orbit

28. Satellite phone - Geosynchronous satellites
Geostationary satellites have a limitation of use in latitude, generally 70 degrees north of the equator to 70 degrees south of the equator. This is a result of look angles being so low on the horizon increasing the chances of terrestrial and other interference from sources in the same frequency bands.

29. Satellite phone - Geosynchronous satellites
Another disadvantage of geostationary satellite systems is that in many areas—even where a large amount of open sky is present—the line-of-sight between the phone and the satellite is broken by obstacles such as steep hills and forest

30. Arthur C. Clarke
Clarke for Geostationary Satellite Communications][ The Arthur C

31. Arthur C. Clarke - Postwar
Although he was not the originator of the concept of geostationary satellites, one of his most important contributions may be his idea that they would be ideal telecommunications relays

32. Arthur C. Clarke - Undersea diving
This, he believed, would make rocket based access to space obsolete and, more than geostationary satellites, would ultimately be his scientific legacy.Personal from Sir Arthur Clarke to Jerry Stone, Director of the Sir Arthur Clarke Awards, 1 November 2006

33. Arthur C. Clarke - The Geostationary communications satellite
Clarke contributed to the popularity of the idea that geostationary satellites would be ideal telecommunications relays

34. Arthur C. Clarke - The Geostationary communications satellite
For example, the concept of geostationary satellites was described in Hermann Oberth's 1923 book Die Rakete zu den Planetenräumen (The Rocket into Interplanetary Space) and then the idea of radio communication with those satellites in Herman Potočnik's (written under the pseudonym Hermann Noordung) 1928 book Das Problem der Befahrung des Weltraums— der Raketen-Motor ([ The Problem of Space Travel—The Rocket Motor]), sections: Providing for Long Distance Communications and Safety and (possibly referring to the idea of relaying messages via satellite, but not that 3 would be optimal) Observing and Researching the Earth's Surface published in Berlin

35. Electrodeless plasma thruster - Applications
Propulsion systems based on electrodeless plasma thrusters seem ideally suited for orbit raising for large geostationary satellites, and would also be able to perform orbital stationkeeping, hence enabling important propellant mass savings. The ability of this technology to provide large thrust density also allows faster missions to the outer planets.

36. Ion thruster - Operational missions
Two geostationary satellites (ESA's Artemis (satellite)|Artemis in and the US military's AEHF-1 in ) have used the ion thruster for orbit raising after the failure of the chemical-propellant engine

37. Geographic coordinate system - Geostationary coordinates
Geostationary satellites (e.g., television satellites) are over the equator at a specific point on Earth, so their position related to Earth is expressed in longitude degrees only. Their latitude is always zero, that is, over the equator.

38. Satellite images - Moving images
In 2005 the Australian company Astrovision (ASX: HZG) announced plans to launch the first commercial geostationary orbit|geostationary satellite in the Asia-Pacific. It is intended to provide true color, real-time live satellite feeds, with down to 250 metres resolution over the entire Asia-Pacific region, from India to Hawaii and Japan to Australia. They were going to provide this content to users of 3G mobile phones, over Pay TV as a weather channel, and to corporate and government users.

39. Last mile - Satellite communications
For information delivery to end users, satellite systems, by nature, have relatively long path lengths, even for low earth-orbiting satellites. They are also very expensive to deploy and therefore each satellite must serve many users. Additionally, the very long paths of geostationary satellites cause information latency that makes many real-time applications unfeasible.

40. Telematics - Trailer tracking
Trailer tracking is the technology of tracking the movements and position of an articulated vehicle's trailer unit, through the use of a location unit fitted to the trailer and a method of returning the position data via mobile communication network or geostationary satellite communications, for use through either PC- or web-based software.

41. NOAA - National Environmental Satellite, Data, and Information Service (NESDIS)
The service operates and manages many geosynchronous satellites and polar orbiting satellites. In 1960 TIROS-1, NOAA's first owned and operated geostationary satellite was launched. In 1983 NOAA assumed operational responsibility for Landsat program|LANDSAT satellite system. In 1984 the Tropical Ocean-Global Atmosphere program (TOGA) program began.

42. Wind - Measurement
Geostationary satellite imagery can be used to estimate the winds throughout the atmosphere based upon how far clouds move from one image to the next

43. Satellite TV - History
ATS-6, the world's first experimental educational and Direct Broadcast Satellite, was launched in The first Soviet geostationary satellite to carry Direct-To-Home television, called Ekran, was launched in 1976.

44. Satellite TV - Technology
Last but not least, there will be a sun outage when the sun lines up directly behind the geostationary satellite the reception antenna is pointing to. This will happen twice a year at around midday for a two-week period and affects both the C-band and the Ku-band. The line-up swamps out all reception for a few minutes due to the sun emitting microwaves on the same frequencies used by the satellite's transponders. This happens in the spring and in the fall.

45. Satellite TV - Technology
The disk will then be capable of receiving any geostationary satellite that is visible at the specific location, i.e

46. Beidou navigation system - Description
BeiDou-2 (formerly known as COMPASS) is not an extension to the older BeiDou-1, but rather supersedes it outright. The new system will be a constellation of 35 satellites, which include 5 geostationary orbit satellites for backward compatibility with BeiDou-1, and 30 non-geostationary satellites (27 in medium earth orbit and 3 in inclined geosynchronous orbit), that will offer complete coverage of the globe.

47. Geosynchronous orbit - History
Geostationary satellites also carry international telephone traffic but they are being replaced by fiber optic cables in heavily populated areas and along the coasts of less developed regions, because of the greater bandwidth available and lower latency, due to the inherent disconcerting delay in communicating via a satellite in such a high orbit

48. GPS-aided geo-augmented navigation - Developments
The first GAGAN transmitter was integrated into the GSAT-4 geostationary orbit|geostationary satellite, and had a goal of being operational in 2008.[ ISRO, Raytheon complete tests for GAGAN Satellite Navigational System.] India Defense Website

49. GPS-aided geo-augmented navigation - Satellites
'GSAT-8' is an Indian geostationary satellites, which was successfully launched using Ariane 5 on 21 May 2011 and is positioned in geosynchronous orbit at 55 degrees E longitude.

50. Wide Area Augmentation System - Ground segment
The reference stations also monitor signals from WAAS geostationary satellites, providing integrity information regarding them as well

51. Wide Area Augmentation System - Space segment
As with the previous satellites, these are leased services under the FAA's Geostationary Satellite Communications Control Segment contract with Lockheed Martin for WAAS geostationary satellite leased services, who is contracted to provide up to three satellites through the year 2016.Federal Aviation Administration (FAA) Announcement [ March 2005] A third satellite was later added to the system

52. Blok D
Blok DM also flies as the third stage for Zenit-3SL rocket, which is used by the Sea Launch project to launch geostationary satellites. In 2002 the failure of a Blok DM3—used in the attempted launch of Astra 1K—caused considerable concern.

53. Quasi-Zenith Satellite System
Its positioning service could also collaborate with the geostationary satellites in Japan's Multi-Functional Transport Satellite (MTSAT), currently under development, which itself is a Satellite Based Augmentation System similar to the U.S

54. Bell TV - Satellites
Bell TV broadcasts from four geostationary satellites: Nimiq 1, 2, 3 and 4iR. Nimiq 4iR is temporary and is being replaced by Nimiq 4. All follow an equatorial path, giving coverage to most of Canada. Nimiq is an Inuktitut language|Inuktitut word for that which unifies and was chosen from a nationwide naming contest in The four satellites are owned and operated by Telesat Canada. Bell's uplink site is located in North York which is in the Toronto area.

55. Geostationary Earth Orbit - Orbital stability
A geostationary orbit can only be achieved at an altitude very close to , and directly above the Equator. This equates to an orbital velocity of or a period of 1,436 minutes, which equates to almost exactly one sidereal day or hours. This ensures that the satellite is locked to the Earth's rotational period and has a stationary Footprint (satellite)|footprint on the ground. All geostationary satellites have to be located on this ring.

56. Geostationary Earth Orbit - Communications
At latitudes above about 81°, geostationary satellites are below the horizon and cannot be seen at all.[ p

57. European Geostationary Navigation Overlay Service
According to specifications, horizontal position accuracy should be better than seven metres. In practice, the horizontal position accuracy is at the metre level. The EGNOS system consists of four geostationary satellites and a network of ground stations.

58. European Geostationary Navigation Overlay Service - Satellites
The use of EGNOS on the ground, especially in urban areas, is limited due to relatively low elevation of geostationary satellites: about 30° above horizon in central Europe and much less in the North of Europe

59. European Geostationary Navigation Overlay Service - Ground stations
* 6 NLES ('N'avigation 'L'and 'E'arth 'S'tations): accuracy and reliability data sending to three geostationary satellite transponders to allow end-user devices to receive them.

60. Compass bearing - Usage
The bearing for geostationary satellites is constant

61. Ocean observations - Future developments
* Satellite observations with higher resolution and accuracy and more spectral bands from geostationary satellites

62. Geostationary Operational Environmental Satellite
The 'Geostationary Satellite' system ('GOES'), operated by the United States NESDIS|National Environmental Satellite, Data, and Information Service (NESDIS), supports weather forecasting, severe storm tracking, and meteorology research

63. Geostationary Operational Environmental Satellite - Satellites
Geostationary satellites cannot ordinarily be seen at all from the poles, but they require station-keeping fuel to keep them stationary over the equator

64. SES S.A.
SES is the world’s second-largest telecommunications satellite operator by revenue and operates a fleet of 55 geostationary satellites able to reach 99% of the World’s population.SES Global Connections via Satellite

65. Hughes Research Laboratories - Notable accomplishments
* HRL began research on ion propulsion in This research led to the Hughes developed xenon ion propulsion system (XIPSTM). XIPS was used as the primary propulsion system on NASA's Deep Space 1 (launched in 1998). It is a standard option for primary stationkeeping on the Hughes/Boeing 601HP (first use: Intelsat 5|PAS-5, 1997) and the 702 (first use: Galaxy-XI, 1999) geostationary satellite families.

66. Aerovironment - Subsidiaries
A single SkyTower platform can provide over 1,000 times the fixed broadband local access capacity of a geostationary satellite using the same frequency band, on a bytes per second per square mile basis.[ David, Leonard, Stratospheric Platform Serves As Satellite], Space.com, July 24, 2002

67. Electric beacon - Distress radiobeacons
When activated, these beacons send out a distress signal that, when detected by geostationary|non-geostationary satellites, can be located by triangulation

68. Solaris Mobile
'Solaris Mobile' is a joint venture company between SES S.A.|SES and Eutelsat Communications to develop and commercialize the first geostationary satellite systems in Europe for broadcasting video, radio and data to in-vehicle receivers and to mobile devices, such as mobile phones, portable media players and PDAs.

69. Solaris Mobile
The services to be developed include video, radio, multimedia data, interactive services, and voice communications. The primary aim is the delivery of mobile television any time, anywhere, and SES and Eutelsat – both successful European satellite operators, providing TV and other services from geostationary satellites to millions of cable and direct-to-home viewers – have so far invested €130m in the venture.

70. Sirius Satellite Radio - SiriusXM for Business
To eliminate this potential problem, Sirius launched a new geostationary satellite, FM-5, to improve service to non-mobile customers such as those of SiriusXM for Business

71. S-DMB
'S-DMB' ('Satellite-DMB') is a hybrid version of the Digital Multimedia Broadcasting. The S-DMB uses the S band ( MHz) of IMT and delivers around 18 channels at 128 kbit/s in 15MHz. It incorporates a high power geostationary satellite, the MBSat 1. For outdoor and light indoor coverage is integrated with a terrestrial repeater (low power gap-filler) network for indoor coverage in urban areas.

72. Darmstadt, Germany - Technology
EUMETSAT, the European Organisation for the Exploitation of Meteorological Satellites, operates the principal European meteorological satellites from its headquarters, including the first and second generations of Meteosat geostationary satellites, and the polar-orbiting Metop series.

73. Lunar space elevator - History
Then in 1966, John Isaacs, a leader of a group of American Oceanographers at Scripps Institution of Oceanography|Scripps Institute, published an article in Science (magazine)|Science about the concept of using thin wires hanging from a geostationary satellite. In that concept, the wires were to be thin (thin wires/tethers are now understood to be more susceptible to micrometeoroid damage). Like Artsutanov, Isaacs’ article also wasn’t well known to the aerospace community.

74. Indian Space Research Organization - The INSAT series
INSAT (Indian National Satellite System) is a series of multipurpose geostationary satellites launched by ISRO to satisfy the telecommunications, broadcasting, meteorology and search-and-rescue needs of India

75. Indian Space Research Organization - Other satellites
ISRO has also launched a set of experimental geostationary satellites known as the GSAT series. Kalpana-1, ISRO's first dedicated meteorological satellite, was launched by the Polar Satellite Launch Vehicle on 12 September The satellite was originally known as MetSat-1. In February 2003 it was renamed to Kalpana-1 by the Indian Prime Minister Atal Bihari Vajpayee in memory of Kalpana Chawla – a NASA astronaut of Indian origin who perished in Space Shuttle Columbia.

76. Indian Space Research Organization - GAGAN
The first GAGAN navigation payload has been fabricated and it was proposed to be flown on GSAT-4 during Apr However, GSAT-4 was not placed in orbit as GSLV-D3 could not complete the mission. Two more GAGAN payloads will be subsequently flown, one each on two geostationary satellites, GSAT-8 and GSAT-10. On 12 May 2012, ISRO announced the successful testing of its indigenous cryogenic engine for 200 seconds for its forthcoming GSLV-D5 flight.

77. LightSquared - Origins
The company has operated in the North American market with two geostationary satellites since 1995

78. Artificial satellite - Early conceptions
The book described geostationary satellites (first put forward by Tsiolkovsky) and discussed communication between them and the ground using radio, but fell short of the idea of using satellites for mass broadcasting and as telecommunications relays.

79. Artificial satellite - Early conceptions
In a 1945 Wireless World article, the English science fiction writer Arthur C. Clarke (1917–2008) described in detail the possible use of communications satellites for mass communications. Clarke examined the logistics of satellite launch, possible orbits and other aspects of the creation of a network of world-circling satellites, pointing to the benefits of high-speed global communications. He also suggested that three geostationary satellites would provide coverage over the entire planet.

80. Artificial satellite - End of life
As of 2002, the FCC requires all geostationary satellites to commit to moving to a graveyard orbit at the end of their operational life prior to launch

81. Malaysian National Space Agency - MEASAT
As of 2006, the MEASAT satellite network consisted of three Geostationary orbit|geostationary satellites designed and built by Boeing Satellite Development Center|Boeing Satellite Systems. MEASAT-1 and MEASAT-2 were launched in 1996 and MEASAT-3 in 2006.

82. SpaceX
Besides NASA contracts, SpaceX has signed contracts with private sector companies, non-American government agencies and the American military for its launch services, filling a growing launch manifest. It has already launched, for a paying customer, a low earth orbiting satellite with its Falcon 1 booster in And on 3 December 2013, the company launched its first commercial geostationary satellite from a Falcon 9.

83. Space debris - Debris at higher altitudes
There has been estimated to be one close (within 50 meters) approach per year.[ Colocation Strategy and Collision Avoidance for the Geostationary Satellites at 19 Degrees West.] CNES Symposium on Space Dynamics, 6–10 November 1989.

84. Space debris - Debris at higher altitudes
Hechler, [ The Collision Probability of Geostationary Satellites] 32nd International Astronautical Congress, 1981, p

85. Space debris - Self-removal
It is an ITU requirement that geostationary satellites be able to remove themselves to a graveyard orbit at the end of their lives. It has been demonstrated that the selected orbital areas do not sufficiently protect GEO lanes from debris, although a response has not yet been formulated.

86. Optus - Network Backbone
** Fleet of geostationary satellites (See Optus fleet of satellites)

87. Equinox - Equinoxes of other planets
For all geostationary orbit|geostationary satellites, there are a few days around the equinox when the sun goes directly behind the satellite relative to Earth (i.e

88. Astronomical interferometer - History of astronomical interferometers
The Navy Optical Interferometer took the first step in this direction in 1996, achieving seminal 3-way synthesis of an image of Mizar (star)|Mizar then; then a first-ever six-way synthesis of Eta Virginis in 2002; and most recently closure phase as a step to the first synthesized images of geostationary satellites.

89. List of English inventions and discoveries - Communications
*The originator of the concept of geostationary satellites for the use of telecommunications relays – Arthur C Clarke

90. Analemma - Analemmas of geosynchronous satellites
A geostationary satellite therefore ideally remains stationary relative to the Earth's surface, staying over a single point on the equator

91. Analemma - Analemmas of geosynchronous satellites
The paraboloidal dishes that are used for radio communication with geosynchronous satellites often have to move so as to follow the satellite's daily movement around its analemma. The mechanisms that drive them must therefore be programmed with the parameters of the analemma. Exceptions are dishes that are used with (approximately) geostationary satellites, since these satellites appear to move so little that a fixed dish can function adequately at all times.

92. BGAN
The network is provided by Inmarsat and uses three geostationary satellites called I-4 satellite|I-4 to provide almost global coverage.

93. BGAN - Signal acquisition
The terminal then needs a line-of-sight to the geostationary satellite so a user would normally be outside, and have a general idea of what direction the satellite would be (with a compass if necessary)

94. Propellant Depot - Space tug alternatives to direct refueling
ViviSat believes their approach is more simple and can operate at lower cost than the MDA propellant transfer approach, while having the technical ability to dock with and service a greater number (90 percent) of the approximately 450 geostationary orbit|geostationary satellites in orbit.

95. Sun outage
A 'sun outage', 'sun transit' or 'sun fade' is an interruption in or distortion of Geosynchronous satellite|geostationary satellite signals caused by interference from solar radiation. The effect is due to the sun's radiation overwhelming the satellite signal.

96. Chandra X-ray Observatory - Technical description
Chandra's highly ellipse|elliptical orbit allows it to observe continuously for up to 55 hours of its 65 hour orbital period. At its furthest orbital point from earth, Chandra is one of the most distant earth-orbiting satellites. This orbit takes it beyond the geostationary satellites and beyond the outer Van Allen belt.

97. Commsat - History
An immediate antecedent of the geostationary satellites was Hughes Aircraft Company|Hughes' Syncom|Syncom 2, launched on July 26, Syncom 2 revolved around the earth once per day at constant speed, but because it still had north-south motion, special equipment was needed to track it.

98. Commsat - Molniya satellites
For areas close to the North (and South) Pole, a geostationary satellite may appear below the horizon

99. Beal Aerospace - Launch Vehicles
The original BA-1 launch vehicle design was intended to service the LEO (Low Earth Orbit) satellite constellation launch market, but was replaced by the much larger BA-2 design when it was decided to concentrate on the more stable Geostationary satellite launch market as the LEO constellations became financially unsound

100. SES S.A.
Accessed August 26, 2014 geostationary satellites able to reach 99% of the World’s population.SES Global Connections via Satellite

101. MVDDS dispute - FCC licensing controversy
Northpoint filed its application in a filing window for non-geostationary satellite systems, and claimed that its terrestrial system was entitled to the same rights given to other applications filed in that window, which employed the same frequency range

102. Global Maritime Distress Safety System - Emergency position-indicating radio beacon (EPIRB)
The original COSPAS/SARSAT system used polar orbiting satellites but in recent years the system has been expanded to also include 4 geostationary satellites

103. Global Maritime Distress Safety System - Sea Area A3
An area, excluding sea areas A1 and A2, within the coverage of an Inmarsat geostationary satellite. This area lies between about latitude 76 Degrees North and South, but excludes A1 and/or A2 designated areas. Inmarsat guarantees their system will work between 70 South and 70 North though it will often work to 76 degrees South or North.

104. Satcom (satellite)
Satcom was one of the early geostationary satellites; the first were the Syncom series, in 1964

105. Geosynchronous satellite
A special case of geosynchronous satellite is the 'geostationary satellite', which has a geostationary orbit – a circular geosynchronous orbit directly above the Earth's equator

106. Geosynchronous satellite
Geostationary satellites have the special property of remaining permanently fixed in exactly the same position in the sky, meaning that ground-based antennas do not need to track them but can remain fixed in one direction

107. Geosynchronous satellite - Application
Geostationary satellites appear to be fixed over one spot above the equator. Receiving and transmitting. Antenna (radio)|antennas on the earth do not need to track such a satellite. These antennas can be fixed in place and are much less expensive than tracking antennas. These satellites have revolutionized global Telecommunication|communications, television broadcasting and weather forecasting, and have a number of important military|defense and intelligence applications.

108. Geosynchronous satellite - Application
Slow start is very slow over a path using a geostationary satellite.

109. Geosynchronous satellite - Application
Another disadvantage of geostationary satellites is the incomplete geographical coverage, since ground stations at higher than roughly 60 degrees latitude have difficulty reliably receiving signals at low elevations

110. Satellite broadcasting - Technology
On occasion, sun outage will occur when the sun lines up directly behind the geostationary satellite the reception antenna is pointing to. This will happen twice a year at around midday for a two-week period in the spring and in the fall, and affects both the C-band and the Ku-band. The line-up swamps out all reception for a few minutes due to the sun emitting microwaves on the same frequencies used by the satellite's transponders.

111. Satellite broadcasting - Early milestones
In 1945 British science fiction writer Arthur C. Clarke proposed a world-wide communications system which would function by means of three satellites equally spaced apart in earth orbit. This was published in the October 1945 issue of the Wireless World magazine and won him the Franklin Institute's Stuart Ballantine Medal in 1963.[ The 1945 Proposal by Arthur C. Clarke for Geostationary Satellite Communications]

112. Satellite broadcasting - Early milestones
The first in a series of Soviet geostationary satellites to carry Direct-To-Home television, Ekran 1, was launched on 26 October It used a 714MHz UHF downlink frequency so that the transmissions could be received with existing UHF television broadcasting|UHF television technology rather than microwave technology.

113. List of broadcast satellites
The major consideration for spacing of geostationary satellites is the beamwidth at-orbit of uplink transmitters, which is primarily a factor of the size and stability of the uplink dish, as well as what frequencies the satellite's transponders receive; satellites with discontiguous frequency allocations can be much closer together.

114. Weather satellite - History
Geostationary satellites followed, beginning with the ATS and SMS series in the late1960s and early1970s, then continuing with the GOES series from the 1970s onward

115. Weather satellite - Geostationary
China operated the Feng-Yun(風雲) geostationary satellites FY-2D at 86.5°E and FY-2E at 123.5°E, which are no longer in use.

116. Space warfare - Practical considerations
Second, space travel involves tremendous speeds by terrestrial standards—a geostationary orbit|geostationary satellite moves at a speed of 3.07km/s whereas objects in low earth orbit can move at up to 8km/s

117. Inmarsat - Global Voice Services
Competing systems such as from Skybitz only operate on the MSAT geostationary satellite over North America.

118. Distress radiobeacon
The signals are monitored worldwide and the location of the distress is detected by non-geostationary satellites, and can be located by some combination of GPS trilateration and doppler effect|doppler triangulation.[ What happens when I activate my beacon?]

119. Distress radiobeacon - Location by Doppler (without GPS)
Local unit terminals (LUTs) detecting non-geostationary satellites interpret the Doppler effect|Doppler frequency shift heard by LEOSAR and MEOSAR satellites as they pass over a beacon transmitting at a fixed frequency

120. Distress radiobeacon - Satellites
Some geosynchronous satellites have beacon receivers. Since the end of 2003 there are four such geostationary satellites (GEOSAR) that cover more than 80% of the surface of the earth. As with all geosynchronous satellites, they are located above the equator. The GEOSAR satellites do not cover the polar caps.

121. Distress radiobeacon - EPIRB sub-classification
* Inmarsat-E – This service ended 1 December 2006; all former users have switched to Category I or II 406MHz EPIRBs. These beacons were float-free, automatically activated EPIRBs operated on 1646MHz. They were detectable by Inmarsat geostationary satellites, and were recognized by GMDSS. See Inmarsat-E.

122. Distress radiobeacon - Obsolete EPIRBs
*Inmarsat E – entered service in The unit is an automatic activation unit operating on 1646MHz and detectable by the Inmarsat geostationary satellite system. This class of EPIRB was approved by the Global Maritime Distress Safety System (GMDSS), but not by the United States. In September 2004, Inmarsat announced that it was terminating its Inmarsat E EPIRB service as of December 2006 due to a lack of interest in the maritime community.

123. Tooway
'Tooway' Satellite Internet access|satellite broadband Internet service available across Europe. The service was launched in 2007 via two Eutelsat Geostationary orbit|geostationary satellites, Hot Bird 6 and Eurobird 3, respectively at the 13° and 33° East orbital positions.

124. Tooway - Services
Tooway services operate over and via Eutelsat's geostationary satellites. This enabled bit rates of 3.6 Mbit/s downstream and 384 kbit/s upstream in Service differentiation is done on volume consumption per month through a Fair Access Policy. When consumption is above volume thresholds, the service remains available but at lower speeds.

125. Direct-broadcast satellite television - Technology
Sun outage occurs when the sun lines up directly between the geostationary satellite the earth station. This happens twice every year around midday for a two-week period in the spring and fall around the equinoxes, and affects both the C-band and the Ku-band. The line-up swamps out all reception for a few minutes due to the sun emitting microwaves on the same frequencies used by the satellite's transponders.

126. TCP tuning - Bandwidth-delay product (BDP)
To give a practical example, two nodes communicating over a geostationary satellite link with a round trip delay of 0.5 seconds and a bandwidth of 10 Gbit/s can have up to 0.5times;1010 bits, i.e., 5 Gbit = 625 megabyte|MB of unacknowledged data in flight

127. Weightlessness - A common misconception
A geostationary satellite is of special interest in this context. Unlike other objects in the sky which rise and set, an object in a geostationary orbit appears motionless in the sky, apparently defying gravity. In fact, it is in a circular equatorial orbit with a period of one day.

128. Central dense overcast - Use as a tropical cyclone strength indicator
Tropical cyclones with maximum sustained winds between and can have their center of circulations obscured by cloudiness within visible and infrared satellite imagery, which makes diagnosis of their intensity a challenge. Winds within tropical cyclones can also be estimated by tracking features within the CDO using rapid scan Weather satellite#Geostationary|geostationary satellite imagery, whose pictures are taken minutes apart rather than every half hour.

129. Satmex - Timeline
May: Telecomm hires Hughes for the construction of the Solidaridad Satellites. It consists of two HS-601 geostationary satellites with tri-axial stabilization, which were designed to provide C-band services in México, the southern United States and the rest of Latin America, with Ku-band services in Mexico and the United States.

130. Satmex - Timeline
The Communications and Transports Secretary (SCT) hires Hughes to build the Mexican satellite system Morelos (two HS-376 geostationary satellites, stabilized by rotation).

131. Svalbard Satellite Station - History
Construction of the road up to Platåberget started in 1996 and a relay station was built to send the data to Isfjord Radio before being sent onwards to a geostationary satellite.Wormdal (2011): 40 The first installation was an parabolic antenna with S and X band capability.

132. Svalbard Satellite Station - Facilities
Their location is based on the need to have as long a line of sight time between the antenna and satellite; a line of sight to a calibration station on Hiorthhamnfjellet and, for communication antennas, a line of sight southwards to see geostationary satellites and a line-of-sight to Isfjord Radio.

133. Hurricane Ava (1973) - Impact and records
However, the meteorological record for the eastern north Pacific is unreliable because geostationary satellite observation did not begin until 1966

134. STS-38 - Classified payload
Rumors that now appear to have been substantiated by the identification of an unknown geostationary satellite by amateur observers [ Ted Molczan, satobs.org: Unknown GEO Object A / Identified as Prowler][ Ted Molczan, satobs.org: Evaluation of the opportunity to launch Prowler on STS-38] insist that a second secret payload was deployed known as Prowler, reportedly a stealth satellite intended to covertly inspect other nation's geostationary satellites.[ Robert Windrem, NBC News: What is America's top-secret spy program?]

135. Synchronous orbit - Examples
Much more commonly, synchronous orbits are employed by artificial satellites used for communication, such as geostationary satellites.

136. Graveyard orbit
A graveyard orbit is used when the change in velocity required to perform a de-orbit Orbital maneuver|maneuver is too high. De-orbiting a geostationary satellite requires a delta-v of about , whereas re-orbiting it to a graveyard orbit only requires about .[ Method for re-orbiting a dual-mode propulsion geostationary spacecraft - Patent # PatentGenius]

137. Graveyard orbit
In order to obtain a license to provide telecommunications services in the United States, the Federal Communications Commission (FCC) requires all geostationary satellites launched after March 18, 2002, to commit to moving to a graveyard orbit at the end of their operational life. U.S. government regulations require a boost, \Delta, of ~300 km.

138. 2012 Atlantic hurricane season - Tropical Storm Florence
Due to a further organized appearance on microwave and geostationary satellite imagery, it is estimated Tropical Depression Six formed at 1800UTC on August3, while located about 130miles (210km) south-southwest of the southernmost islands of Cape Verde

139. Nimiq
The 'Nimiq' satellites are a fleet of Geostationary satellite|geostationary telecommunications satellites owned by the Telesat and used by satellite television providers including Bell TV and EchoStar (Dish Network). 'Nimiq' is an Inuktitut language|Inuit word used for an object or a force which binds things together. A contest in 1998 was held to choose the name of these satellites. The contest drew over 36,000 entries.

140. Astra 1KR
'Astra 1KR' is one of the Astra (satellites)|Astra geostationary satellites owned by SES S.A.|SES. It was launched in April 2006 as a replacement for Astra 1K, which failed to reach orbit on launch in The launch of Astra 1KR was the first attempted by SES since the Astra 1K failure.

141. Hellas Sat
'Hellas-Sat Consortium Limited' (Hellas-Sat) is the owner and a wholesaler of capacity and services of the Greek/Cypriot Hellas-Sat-2 satellite, an Astrium Eurostar E2000+, which was launched successfully on 13 May, 2003 to the 39th meridian east|39° E orbital position in the Geostationary orbit|Geostationary Satellite Orbit.

142. Row 44 - The System
Row 44's fuselage-top-mounted Ku-band antennas communicate with geostationary satellites, allowing Row 44 to offer uninterrupted in-flight Wi-Fi service over water and on airlines' routes virtually anywhere in the world.

143. OnAir - Inmarsat SwiftBroadband (L band)
A satellite data unit (SDU) manufactured by Thales Group|Thales and branded TopConnect establishes a Backhaul (telecommunications)|backhaul link to the ground through Inmarsat's SwiftBroadband Geostationary orbit|geostationary satellite constellation operating in the L band around 1500MHz which allows the use of electronically steerable antennas mounted atop the aircraft fuselage and encased within a fiberglass, RF-transparent radome

144. India–Pakistan relations - Technology and education
In 2008, India's ISRO scored a great international success by launching its moon probe, Chandrayaan-1 in 2008, and continues to advance its space program and enhancement of science and technology in India.See: Chandrayaan-2 With technical assistance from Peoples Republic of China|China, Pakistan launched its first geostationary satellite, Paksat-1R in 2011.See Paksat-1R

145. For More Information, Visit:
The Art of Service