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85-460: The Anik satellites are a series of geostationary communications satellites launched for Telesat Canada for television , voice and data in Canada and other parts of the world, from 1972 through 2013. Some of the later satellites in the series remain operational in orbit, while others have been retired to a graveyard orbit . The naming of the satellite was determined by a national contest, and
170-591: A Diamant A rocket launched from the CIEES site at Hammaguir , Algeria . With Astérix, France became the sixth country to have an artificial satellite. Early satellites were built to unique designs. With advancements in technology, multiple satellites began to be built on single model platforms called satellite buses . The first standardized satellite bus design was the HS-333 geosynchronous (GEO) communication satellite launched in 1972. Beginning in 1997, FreeFlyer
255-571: A GPS / WAAS payload in addition to the C-band and Ku-band transponders. The GPS /WAAS Payload was disabled on May 15, 2022, in concert with the activation of Galaxy XV. At 5,900 kilograms (13,000 lb), it is more than ten times the size of Anik A2 and is one of the largest, most powerful communications satellites ever built. Anik F2 is a Boeing 702 -series satellite, designed to support and enhance current North American voice, data, and broadcast services with its C-Band and Ku-band technologies. It
340-414: A catalyst . The most commonly used propellant mixtures on satellites are hydrazine -based monopropellants or monomethylhydrazine – dinitrogen tetroxide bipropellants. Ion thrusters on satellites usually are Hall-effect thrusters , which generate thrust by accelerating positive ions through a negatively-charged grid. Ion propulsion is more efficient propellant-wise than chemical propulsion but its thrust
425-468: A geosynchronous network is a communication network based on communication with or through geosynchronous satellites. The term geosynchronous refers to the satellite's orbital period which enables it to be matched, with the rotation of the Earth ("geo-"). Along with this orbital period requirement, to be geostationary as well, the satellite must be placed in an orbit that puts it in the vicinity over
510-761: A halo orbit , three for a Lissajous orbit ). Earth observation satellites gather information for reconnaissance , mapping , monitoring the weather , ocean, forest, etc. Space telescopes take advantage of outer space's near perfect vacuum to observe objects with the entire electromagnetic spectrum . Because satellites can see a large portion of the Earth at once, communications satellites can relay information to remote places. The signal delay from satellites and their orbit's predictability are used in satellite navigation systems, such as GPS. Space probes are satellites designed for robotic space exploration outside of Earth, and space stations are in essence crewed satellites. The first artificial satellite launched into
595-409: 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
680-591: A Satellite Vehicle", by R. R. Carhart. This expanded on potential scientific uses for satellite vehicles and was followed in June 1955 with "The Scientific Use of an Artificial Satellite", by H. K. Kallmann and W. W. Kellogg. The first artificial satellite was Sputnik 1 , launched by the Soviet Union on 4 October 1957 under the Sputnik program , with Sergei Korolev as chief designer. Sputnik 1 helped to identify
765-453: A U.S. Scout rocket from Wallops Island (Virginia, United States) with an Italian launch team trained by NASA . In similar occasions, almost all further first national satellites were launched by foreign rockets. France was the third country to launch a satellite on its own rocket. On 26 November 1965, the Astérix or A-1 (initially conceptualized as FR.2 or FR-2), was put into orbit by
850-405: A bandwidth of tens of megahertz. Satellites are placed from the surface to the orbit by launch vehicles , high enough to avoid orbital decay by the atmosphere . Satellites can then change or maintain the orbit by propulsion , usually by chemical or ion thrusters . As of 2018, about 90% of the satellites orbiting the Earth are in low Earth orbit or geostationary orbit ; geostationary means
935-644: A few hours, Telesat managed to restore normal functions on Anik E1 at 00:15 UTC, on 21 January 1994. At 01:00 UTC, both the primary and redundant Anik E2 momentum wheels failed, thus eliminating the gyroscope effect that helps keep the satellite pointed correctly towards Earth. The exact problem lay with the circuitry having to do with the stabilizing momentum wheel . Anik E2 was not restored to service for five months; users had to relocate services to Anik E1 and reposition satellite dishes; for some users, such as Northwestel in northern Canada , it meant days of flying technicians from one community to another to reposition
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#17327929388821020-399: A loss of Northwestel's long distance and cellular service, Xplornet and some of SSI Micro Internet, and some TV signals for Shaw Direct Satellite TV . Anik F2 has lost two of its four thrusters. As a result, continued operation uses significantly more fuel. Telesat has announced that it is acquiring an in-orbit satellite to replace Anik F2. An FCC filing by Telesat has since revealed that
1105-484: A method of communication to ground stations , called transponders . Many satellites use a standardized bus to save cost and work, the most popular of which are small CubeSats . Similar satellites can work together as groups, forming constellations . Because of the high launch cost to space, most satellites are designed to be as lightweight and robust as possible. Most communication satellites are radio relay stations in orbit and carry dozens of transponders, each with
1190-452: A number of proprietary satellite data protocols that are designed to proxy TCP/IP connections over long-delay satellite links—these are marketed as being a partial solution to the poor performance of native TCP over satellite links. TCP presumes that all loss is due to congestion, not errors, and probes link capacity with its " slow start " algorithm , which only sends packets once it is known that earlier packets have been received. Slow start
1275-596: A permanent loss of half the satellite's power. Anik F1 is a Canadian geosynchronous communications satellite that was launched on November 21, 2000, by an Ariane 4 rocket from the European Space Agency Centre Spatial Guyanais at Kourou . At the moment of its launch it was the most powerful communications satellite ever built. It has an advanced xenon ion thruster propulsion system and its communication "footprint" covers Central America as well as North America . It
1360-418: A satellite's lifetime. Resource use is difficult to monitor and quantify for satellites and launch vehicles due to their commercially sensitive nature. However, aluminium is a preferred metal in satellite construction due to its lightweight and relative cheapness and typically constitutes around 40% of a satellite's mass. Through mining and refining, aluminium has numerous negative environmental impacts and
1445-449: A thin cable called a tether . Recovery satellites are satellites that provide a recovery of reconnaissance, biological, space-production and other payloads from orbit to Earth. Biosatellites are satellites designed to carry living organisms, generally for scientific experimentation. Space-based solar power satellites are proposed satellites that would collect energy from sunlight and transmit it for use on Earth or other places. Since
1530-600: A thought experiment by Isaac Newton to explain the motion of natural satellites , in his Philosophiæ Naturalis Principia Mathematica (1687). The first fictional depiction of a satellite being launched into orbit was a short story by Edward Everett Hale , " The Brick Moon " (1869). The idea surfaced again in Jules Verne 's The Begum's Fortune (1879). In 1903, Konstantin Tsiolkovsky (1857–1935) published Exploring Space Using Jet Propulsion Devices , which
1615-400: Is a commercial off-the-shelf software application for satellite mission analysis, design, and operations. After the late 2010s, and especially after the advent and operational fielding of large satellite internet constellations —where on-orbit active satellites more than doubled over a period of five years—the companies building the constellations began to propose regular planned deorbiting of
1700-434: Is a result of their high altitude: radio signals take approximately 0.25 of a second to reach and return from the satellite, resulting in a small but significant signal delay . This delay increases the difficulty of telephone conversation and reduces the performance of common network protocols such as TCP/IP , but does not present a problem with non-interactive systems such as satellite television broadcasts. There are
1785-631: Is also the first commercial satellite with a substantial X-band payload for government communications over the Americas and the Pacific Ocean including Hawaii . The satellite will be positioned at 107.3° West longitude where it will be co-located with Telesat's Anik F1 satellite, doubling both the C-band and Ku-band transponders serving South America from the 107.3° West orbital location. Satellite A satellite or artificial satellite
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#17327929388821870-721: Is an object, typically a spacecraft , placed into orbit around a celestial body . They have a variety of uses, including communication relay, weather forecasting , navigation ( GPS ), broadcasting , scientific research, and Earth observation. Additional military uses are reconnaissance, early warning , signals intelligence and, potentially, weapon delivery. Other satellites include the final rocket stages that place satellites in orbit and formerly useful satellites that later become defunct. Except for passive satellites , most satellites have an electricity generation system for equipment on board, such as solar panels or radioisotope thermoelectric generators (RTGs). Most satellites also have
1955-610: Is currently unclear. The visibility of man-made objects in the night sky may also impact people's linkages with the world, nature, and culture. At all points of a satellite's lifetime, its movement and processes are monitored on the ground through a network of facilities. The environmental cost of the infrastructure as well as day-to-day operations is likely to be quite high, but quantification requires further investigation. Particular threats arise from uncontrolled de-orbit. Some notable satellite failures that polluted and dispersed radioactive materials are Kosmos 954 , Kosmos 1402 and
2040-399: Is dependent on rocket design and fuel type. The amount of green house gases emitted by rockets is considered trivial as it contributes significantly less, around 0.01%, than the aviation industry yearly which itself accounts for 2-3% of the total global greenhouse gas emissions. Rocket emissions in the stratosphere and their effects are only beginning to be studied and it is likely that
2125-473: Is deployed for military or intelligence purposes, it is known as a spy satellite or reconnaissance satellite. Their uses include early missile warning, nuclear explosion detection, electronic reconnaissance, and optical or radar imaging surveillance. Navigational satellites are satellites that use radio time signals transmitted to enable mobile receivers on the ground to determine their exact location. The relatively clear line of sight between
2210-608: Is known as an inclined orbit . It will appear (when viewed by someone on the ground) to oscillate daily around a fixed point. As the angle between the orbit and the equator decreases, the magnitude of this oscillation becomes smaller; when the orbit lies entirely over the equator in a circular orbit, the satellite remains stationary relative to the Earth's surface – it is said to be geostationary . As of October 2018 , there are approximately 446 active geosynchronous satellites, some of which are not operational. Geostationary satellites appear to be fixed over one spot above
2295-517: Is most used in archaeology , cartography , environmental monitoring , meteorology , and reconnaissance applications. As of 2021, there are over 950 Earth observation satellites, with the largest number of satellites operated with Planet Labs . Weather satellites monitor clouds , city lights , fires , effects of pollution , auroras , sand and dust storms , snow cover, ice mapping, boundaries of ocean currents , energy flows, etc. Environmental monitoring satellites can detect changes in
2380-581: Is one of the most carbon-intensive metals. Satellite manufacturing also requires rare elements such as lithium , gold , and gallium , some of which have significant environmental consequences linked to their mining and processing and/or are in limited supply. Launch vehicles require larger amounts of raw materials to manufacture and the booster stages are usually dropped into the ocean after fuel exhaustion. They are not normally recovered. Two empty boosters used for Ariane 5 , which were composed mainly of steel, weighed around 38 tons each, to give an idea of
2465-636: Is required to receive the weaker (as compared to the stronger Ku DBS band used by Dish and DirecTV as their primary satellites) Ku FSS band reliably. Also, Dish uses a specially designed "combo" LNB that houses both elements necessary to receive Dish services from both 118 and 119 taking the space of only a single LNB. The combo LNB is also available part of a single LNBF unit that can also receive additional Dish programming at 110 and 129 satellite locations for reception of Dish's entire Western Arc constellation of satellites providing both SD and HD content. Dish does not produce any 118 only LNBF's for its systems, only
2550-611: Is the geostationary satellite , which has a geostationary orbit – a circular geosynchronous orbit directly above the Earth's equator . Another type of geosynchronous orbit used by satellites is the Tundra elliptical orbit . Geostationary satellites have the unique property of remaining permanently fixed in exactly the same position in the sky as viewed from any fixed location on Earth, meaning that ground-based antennas do not need to track them but can remain fixed in one direction. Such satellites are often used for communication purposes ;
2635-430: Is the chemical propellant used which then releases ammonia , hydrogen and nitrogen as gas into the upper atmosphere. Also, the environment of the outer atmosphere causes the degradation of exterior materials. The atomic oxygen in the upper atmosphere oxidises hydrocarbon-based polymers like Kapton , Teflon and Mylar that are used to insulate and protect the satellite which then emits gasses like CO 2 and CO into
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2720-427: Is the fifteenth satellite to be launched by Telesat Canada. With its use of Ka band technology, low-cost two-way satellite delivery will be available for wireless Internet access connections, telehealth , distance education , remote work applications, and e-commerce in the most remote regions of Canada. On October 6, 2011, starting around 06:30 EST a "technical" anomaly caused the satellite to point away from
2805-488: Is very slow over a path using a geostationary satellite. RFC 2488, written in 1999, gives several suggestions on this issue. There are some advantages of geo-stationary satellites: A 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. Satellite dishes at such high latitudes would need to be pointed almost directly towards
2890-425: Is very small (around 0.5 N or 0.1 lb f ), and thus requires a longer burn time. The thrusters usually use xenon because it is inert , can be easily ionized , has a high atomic mass and storable as a high-pressure liquid. Most satellites use solar panels to generate power, and a few in deep space with limited sunlight use radioisotope thermoelectric generators . Slip rings attach solar panels to
2975-912: The American Rocket Society , the National Science Foundation , and the International Geophysical Year, the Army and Navy worked on Project Orbiter with two competing programs. The army used the Jupiter C rocket , while the civilian–Navy program used the Vanguard rocket to launch a satellite. Explorer 1 became the United States' first artificial satellite, on 31 January 1958. The information sent back from its radiation detector led to
3060-586: The Chinese military shot down an aging weather satellite, followed by the US Navy shooting down a defunct spy satellite in February 2008. On 18 November 2015, after two failed attempts, Russia successfully carried out a flight test of an anti-satellite missile known as Nudol . On 27 March 2019, India shot down a live test satellite at 300 km altitude in 3 minutes, becoming the fourth country to have
3145-726: The HS-376 of Hughes design. Anik E1 and Anik E2 were launched in the early 1990s to replace Anik D1 and Anik D2. Unlike the cylinder-shaped spin-stabilised satellites of the D-series, these were cubical, 3-axis satellites using momentum wheels for attitude stabilisation. Anik E2 experienced an anomaly during deployment of its C-band antenna, which was successfully deployed after several corrective maneuvers. On Thursday, January 20, 1994, Anik E1 and Anik E2 suffered problems due to solar activity. Anik E1 failed first at 17:50 UTC, knocking out satellite-delivered television signals in Canada. After
3230-627: The Netherlands , Norway , Pakistan , Poland , Russia , Saudi Arabia , South Africa , Spain , Switzerland , Thailand , Turkey , Ukraine , the United Kingdom and the United States , had some satellites in orbit. Japan's space agency (JAXA) and NASA plan to send a wooden satellite prototype called LingoSat into orbit in the summer of 2024. They have been working on this project for few years and sent first wood samples to
3315-470: The Transit 5-BN-3 . When in a controlled manner satellites reach the end of life they are intentionally deorbited or moved to a graveyard orbit further away from Earth in order to reduce space debris . Physical collection or removal is not economical or even currently possible. Moving satellites out to a graveyard orbit is also unsustainable because they remain there for hundreds of years. It will lead to
3400-576: The White House announced on 29 July 1955 that the U.S. intended to launch satellites by the spring of 1958. This became known as Project Vanguard . On 31 July, the Soviet Union announced its intention to launch a satellite by the fall of 1957. Sputnik 2 was launched on 3 November 1957 and carried the first living passenger into orbit, a dog named Laika . The dog was sent without possibility of return. In early 1955, after being pressured by
3485-446: The "father of the geosynchronous satellite", Harold Rosen , an engineer at Hughes Aircraft Company, invented the first operational geosynchronous satellite, Syncom 2 . It was launched on a Delta rocket B booster from Cape Canaveral July 26, 1963. The first geostationary communication satellite was Syncom 3 , launched on August 19, 1964, with a Delta D launch vehicle from Cape Canaveral. The satellite, in orbit approximately above
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3570-596: The Earth and positioned itself towards the Sun in order to keep critical systems running. This was Anik F2's first outage. The event caused the Canadian military's research arm, Defence Research and Development Canada , to start considering satellites as critical infrastructure systems and to invest in research to develop innovations that will help protect Canadian satellites from failures. On October 2, 2016, at approximately 17:00 EDT, another malfunction with Anik F2 resulted in
3655-514: The Earth causing an outage in Internet, telephone and bank machine connectivity throughout much of Canada's northern areas. The outage also affected flights in the region. Some hospitals in Québec reported an outage in their communications systems as a result of the satellite outage. The anomaly was caused when the satellite did not respond well to a software update. As it failed, it turned away from
3740-457: The Earth's vegetation , atmospheric trace gas content, sea state, ocean color, and ice fields. By monitoring vegetation changes over time, droughts can be monitored by comparing the current vegetation state to its long term average. Anthropogenic emissions can be monitored by evaluating data of tropospheric NO 2 and SO 2 . A communications satellite is an artificial satellite that relays and amplifies radio telecommunication signals via
3825-417: The Earth's orbit was the Soviet Union 's Sputnik 1 , on October 4, 1957. As of December 31, 2022, there are 6,718 operational satellites in the Earth's orbit, of which 4,529 belong to the United States (3,996 commercial), 590 belong to China, 174 belong to Russia, and 1,425 belong to other nations. The first published mathematical study of the possibility of an artificial satellite was Newton's cannonball ,
3910-500: The Earth, called remote sensing . Most Earth observation satellites are placed in low Earth orbit for a high data resolution, though some are placed in a geostationary orbit for an uninterrupted coverage. Some satellites are placed in a Sun-synchronous orbit to have consistent lighting and obtain a total view of the Earth. Depending on the satellites' functions, they might have a normal camera , radar , lidar , photometer , or atmospheric instruments. Earth observation satellite's data
3995-553: The Moon and the Sun. Satellites utilize ultra-white reflective coatings to prevent damage from UV radiation. Without orbit and orientation control, satellites in orbit will not be able to communicate with ground stations on the Earth. Chemical thrusters on satellites usually use monopropellant (one-part) or bipropellant (two-parts) that are hypergolic . Hypergolic means able to combust spontaneously when in contact with each other or to
4080-455: The atmosphere. Given the current surge in satellites in the sky, soon hundreds of satellites may be clearly visible to the human eye at dark sites. It is estimated that the overall levels of diffuse brightness of the night skies has increased by up to 10% above natural levels. This has the potential to confuse organisms, like insects and night-migrating birds, that use celestial patterns for migration and orientation. The impact this might have
4165-603: The atmosphere. For example, SpaceX Starlink satellites, the first large satellite internet constellation to exceed 1000 active satellites on orbit in 2020, are designed to be 100% demisable and burn up completely on their atmospheric reentry at the end of their life, or in the event of an early satellite failure. In different periods, many countries, such as Algeria , Argentina , Australia , Austria , Brazil , Canada , Chile , China , Denmark , Egypt , Finland , France , Germany , India , Iran , Israel , Italy , Japan , Kazakhstan , South Korea , Malaysia , Mexico ,
4250-447: The capability to destroy live satellites. The environmental impact of satellites is not currently well understood as they were previously assumed to be benign due to the rarity of satellite launches. However, the exponential increase and projected growth of satellite launches are bringing the issue into consideration. The main issues are resource use and the release of pollutants into the atmosphere which can happen at different stages of
4335-514: The combo 118/119 by itself or as part of a single unit that also receives other Dish satellites. The launch of Anik G1 was announced by Telesat on April 16, 2013. Anik G1 is a multi-mission satellite with three different payloads that will provide direct-to-home (DTH) television service in Canada, as well as broadband, voice, data, and video services in South America where economic growth has driven high demand for satellite services. It
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#17327929388824420-537: The company is buying AMC-11 from SES. Once the FCC has issued its permit, Telesat can take over AMC-11 and move it to 111.1° West. It will be renamed Anik F4. According to SatNews Publishers, Anik F3 is a 4,634 kilograms (10,216 lb) broadcasting and telecommunications satellite which will provide direct-to-home television in the United States, broadband Internet and telecommunications for Bell Canada , and broadcast TV in northern and other remote areas of Canada. It
4505-551: The density of high atmospheric layers through measurement of its orbital change and provided data on radio-signal distribution in the ionosphere . The unanticipated announcement of Sputnik 1's success precipitated the Sputnik crisis in the United States and ignited the so-called Space Race within the Cold War . In the context of activities planned for the International Geophysical Year (1957–1958),
4590-546: The discovery of the Earth's Van Allen radiation belts . The TIROS-1 spacecraft, launched on April 1, 1960, as part of NASA's Television Infrared Observation Satellite (TIROS) program, sent back the first television footage of weather patterns to be taken from space. In June 1961, three and a half years after the launch of Sputnik 1, the United States Space Surveillance Network cataloged 115 Earth-orbiting satellites. While Canada
4675-403: The dishes. Telesat ultimately restored Anik E2 by constructing special earth stations at each end of the country to monitor the satellite's position, and designed specialised software to use a combination of its control jets and magnetic torquing coils to finely position the satellite. Even though a small amount of extra stationkeeping fuel was needed for pitch control, the efficiencies from using
4760-484: The earth's climate. After deorbiting 70% of satellites end up in the ocean and are rarely recovered. Using wood as an alternative material has been posited in order to reduce pollution and debris from satellites that reenter the atmosphere. Space debris pose dangers to the spacecraft (including satellites) in or crossing geocentric orbits and have the potential to drive a Kessler syndrome which could potentially curtail humanity from conducting space endeavors in
4845-427: The equator. Receiving and transmitting 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 communications , television broadcasting and weather forecasting , and have a number of important defense and intelligence applications. One disadvantage of geostationary satellites
4930-402: The equator. These two requirements make the satellite appear in an unchanging area of visibility when viewed from the Earth's surface, enabling continuous operation from one point on the ground. The special case of a geostationary orbit is the most common type of orbit for communications satellites. If a geosynchronous satellite's orbit is not exactly aligned with the Earth's equator , the orbit
5015-444: The further pollution of space and future issues with space debris. When satellites deorbit much of it is destroyed during re-entry into the atmosphere due to the heat. This introduces more material and pollutants into the atmosphere. There have been concerns expressed about the potential damage to the ozone layer and the possibility of increasing the earth's albedo , reducing warming but also resulting in accidental geoengineering of
5100-414: The future. Geosynchronous satellite A geosynchronous satellite is a satellite in geosynchronous orbit , with an orbital period the same as the Earth's rotation period. Such a satellite returns to the same position in the sky after each sidereal day , and over the course of a day traces out a path in the sky that is typically some form of analemma . A special case of geosynchronous satellite
5185-527: The horizon. The signals would have to pass through the largest amount of atmosphere, and could even be blocked by land topography, vegetation or buildings. In the USSR , a practical solution was developed for this problem with the creation of special Molniya / Orbita inclined path satellite networks with elliptical orbits. Similar elliptical orbits are used for the Sirius Radio satellites. The concept
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#17327929388825270-412: The impact of regulated ozone-depleting substances. Whilst emissions of water vapour are largely deemed as inert, H 2 O is the source gas for HO x and can also contribute to ozone loss through the formation of ice particles. Black carbon particles emitted by rockets can absorb solar radiation in the stratosphere and cause warming in the surrounding air which can then impact the circulatory dynamics of
5355-462: The impacts will be more critical than emissions in the troposphere. The stratosphere includes the ozone layer and pollutants emitted from rockets can contribute to ozone depletion in a number of ways. Radicals such as NO x , HO x , and ClO x deplete stratospheric O 3 through intermolecular reactions and can have huge impacts in trace amounts. However, it is currently understood that launch rates would need to increase by ten times to match
5440-449: The magnetic coils for roll-yaw adjustment compensated for fuel usage that would have been used in those axes, so there was an insignificant overall effect on fuel use throughout the life of the satellite. The Anik E2 satellite continued to provide full service for 14 years; two years longer than its design life of 12 years. On March 26, 1996, another catastrophic failure occurred. A critical diode on Anik E1's solar panel shorted out, causing
5525-400: The mid-2000s, satellites have been hacked by militant organizations to broadcast propaganda and to pilfer classified information from military communication networks. For testing purposes, satellites in low earth orbit have been destroyed by ballistic missiles launched from the Earth. Russia , United States , China and India have demonstrated the ability to eliminate satellites. In 2007,
5610-725: The most potent scientific tools of the Twentieth Century." The United States had been considering launching orbital satellites since 1945 under the Bureau of Aeronautics of the United States Navy . Project RAND eventually released the report, but considered the satellite to be a tool for science, politics, and propaganda, rather than a potential military weapon. In 1946, American theoretical astrophysicist Lyman Spitzer proposed an orbiting space telescope . In February 1954, Project RAND released "Scientific Uses for
5695-557: The older satellites that reached the end of life , as a part of the regulatory process of obtaining a launch license. The largest artificial satellite ever is the International Space Station . By the early 2000s, and particularly after the advent of CubeSats and increased launches of microsats —frequently launched to the lower altitudes of low Earth orbit (LEO)—satellites began to more frequently be designed to get destroyed, or breakup and burnup entirely in
5780-550: The possible use of communications satellites for mass communications. He suggested that three geostationary satellites would provide coverage over the entire planet. In May 1946, the United States Air Force 's Project RAND released the Preliminary Design of an Experimental World-Circling Spaceship , which stated "A satellite vehicle with appropriate instrumentation can be expected to be one of
5865-538: The power output of the Anik A series. Anik C also allowed a significant increase in telecommunications capacity over Anik A. Each Anik C satellite had sixteen Ku-band transponders. Anik C3 was used to distribute Canada's first pay television networks -- First Choice , Superchannel , C-Channel , Star Channel, AIM Pay-TV since February 1983. Anik C3 transponder lineup (1983): Anik D1 and Anik D2 series C-Band satellites were launched in 1982 and 1984. They were based on
5950-412: The quantity of materials that are often left in the ocean. Rocket launches release numerous pollutants into every layer of the atmosphere, especially affecting the atmosphere above the tropopause where the byproducts of combustion can reside for extended periods. These pollutants can include black carbon , CO 2 , nitrogen oxides (NO x ), aluminium and water vapour , but the mix of pollutants
6035-427: 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. When an Earth observation satellite or a communications satellite
6120-409: The satellite; the slip rings can rotate to be perpendicular with the sunlight and generate the most power. All satellites with a solar panel must also have batteries , because sunlight is blocked inside the launch vehicle and at night. The most common types of batteries for satellites are lithium-ion , and in the past nickel–hydrogen . Earth observation satellites are designed to monitor and survey
6205-404: The satellites and receivers on the ground, combined with ever-improving electronics, allows satellite navigation systems to measure location to accuracies on the order of a few meters in real time. Astronomical satellites are satellites used for observation of distant planets, galaxies, and other outer space objects. Tether satellites are satellites that are connected to another satellite by
6290-490: The satellites stay still in the sky (relative to a fixed point on the ground). Some imaging satellites chose a Sun-synchronous orbit because they can scan the entire globe with similar lighting. As the number of satellites and space debris around Earth increases, the threat of collision has become more severe. A small number of satellites orbit other bodies (such as the Moon , Mars , and the Sun ) or many bodies at once (two for
6375-408: The satellites was equipped with 12 C-band transponders , and thus had the capacity for 12 colour television channels. Three channels were allocated for CBC, two to TCTS and CNCP Telecommunications , two to Bell Canada , one for Canadian Overseas Telecommunications . Two channels were to put on reserve and the remaining two were unallocated (future use). It was launched on December 15, 1978, and
6460-540: The space in 2021 to test the material's resilience to space conditions. Most satellites use chemical or ion propulsion to adjust or maintain their orbit , coupled with reaction wheels to control their three axis of rotation or attitude. Satellites close to Earth are affected the most by variations in the Earth's magnetic , gravitational field and the Sun's radiation pressure ; satellites that are further away are affected more by other bodies' gravitational field by
6545-458: The special conditions of space could be useful for scientific experiments. The book described geostationary satellites (first put forward by Konstantin Tsiolkovsky ) and discussed the communication between them and the ground using radio, but fell short with the idea of using satellites for mass broadcasting and as telecommunications relays. In a 1945 Wireless World article, English science fiction writer Arthur C. Clarke described in detail
6630-459: The stratosphere. Both warming and changes in circulation can then cause depletion of the ozone layer. Several pollutants are released in the upper atmospheric layers during the orbital lifetime of LEO satellites. Orbital decay is caused by atmospheric drag and to keep the satellite in the correct orbit the platform occasionally needs repositioning. To do this nozzle-based systems use a chemical propellant to create thrust. In most cases hydrazine
6715-509: Was built by EADS Astrium and launched on a Proton-M rocket. It was successfully placed into orbit by International Launch Services , who also launched Anik F1R, Nimiq 1 and Nimiq 2. However, previous to launch, it was announced that Dish would be leasing the entire capacity of Anik F3 for its entire estimated life of approximately 15 years. Today, Anik F3 is used by Dish to beam its "international" foreign language channel offerings. A slightly larger reflector provided by Dish to its customers
6800-474: Was first proposed by Herman Potočnik in 1928 and popularised by the science fiction author Arthur C. Clarke in a paper in Wireless World in 1945. Working prior to the advent of solid-state electronics, Clarke envisioned a trio of large, crewed space stations arranged in a triangle around the planet. Modern satellites are numerous, uncrewed, and often no larger than an automobile. Widely known as
6885-534: Was launched for Telesat Canada , a Canadian communications company. The primary customers are the Canadian Broadcasting Corporation , Shaw Direct , CHUM Limited and Canadian Satellite Communications Inc. , and Bell Canada Enterprise Inc. The solar panels of Anik F1 degraded more rapidly than expected, and a replacement Anik F1R was launched in 2005, with Anik F1 switching to serving only South America [2] . Anik F1R also carries
6970-426: Was the first academic treatise on the use of rocketry to launch spacecraft. He calculated the orbital speed required for a minimal orbit, and inferred that a multi-stage rocket fueled by liquid propellants could achieve this. Herman Potočnik explored the idea of using orbiting spacecraft for detailed peaceful and military observation of the ground in his 1928 book, The Problem of Space Travel . He described how
7055-517: Was the successor to the Anik A series and Hermes (aka Communications Technology Satellite , or CTS) experimental satellite. Most of the transponders were devoted to CBC Television — East and West feeds of CBC North , CBC Parliamentary Television Network , CITV-TV Edmonton, CHCH Hamilton, and TVOntario . CNCP Telecommunications also used Anik B as a relay for its services. The Globe and Mail used Anik B to transmit copy to printing plants across Canada. The Anik C satellite series tripled
7140-483: Was the third country to build a satellite which was launched into space, it was launched aboard an American rocket from an American spaceport. The same goes for Australia, whose launch of the first satellite involved a donated U.S. Redstone rocket and American support staff as well as a joint launch facility with the United Kingdom. The first Italian satellite San Marco 1 was launched on 15 December 1964 on
7225-483: Was won by Julie-Frances Czapla of Saint-Léonard, Québec . In Inuktitut , Anik means "brother". The Anik A satellites were the world's first national domestic satellites. (Prior to Anik A1's launch, all geosynchronous communications satellites were transcontinental, i.e. Intelsat I and others.) The Anik A fleet of three satellites gave CBC the ability to reach the Canadian North for the first time. Each of
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