Satellite
In the context of spaceflight, a satellite is an object that has been intentionally placed into orbit. These objects are called artificial satellites to distinguish them from natural satellites such as Earth's Moon.
On 4 October 1957 the Soviet Union launched the world's first artificial satellite, Sputnik 1. Since then, about 8,900 satellites from more than 40 countries have been launched. According to a 2018 estimate, some 5,000 remain in orbit. Of those about 1,900 were operational, while the rest have lived out their useful lives and become space debris. Approximately 63% of operational satellites are in low Earth orbit, 6% are in medium-Earth orbit, 29% are in geostationary orbit and the remaining 2% are in elliptic orbit. In terms of countries with the most satellites the USA significantly leads the way with 859 satellites, China is second with 250, and Russia third with 146. These are then followed by Japan, India and the UK.
A few large space stations have been launched in parts and assembled in orbit. Over a dozen space probes have been placed into orbit around other bodies and become artificial satellites of the Moon, Mercury, Venus, Mars, Jupiter, Saturn, a few asteroids, a comet and the Sun.
Satellites are used for many purposes. Among several other applications, they can be used to make star maps and maps of planetary surfaces, and also take pictures of planets they are launched into. Common types include military and civilian Earth observation satellites, communications satellites, navigation satellites, weather satellites, and space telescopes. Space stations and human spacecraft in orbit are also satellites.
Satellites can operate by themselves or as part of a larger system, a satellite formation or satellite constellation.
Satellite orbits vary greatly, depending on the purpose of the satellite, and are classified in a number of ways. Well-known classes include low Earth orbit, polar orbit, and geostationary orbit.
A launch vehicle is a rocket that places a satellite into orbit. Usually, it lifts off from a launch pad on land. Some are launched at sea from a submarine or a mobile maritime platform, or aboard a plane.
Satellites are usually semi-independent computer-controlled systems. Satellite subsystems attend many tasks, such as power generation, thermal control, telemetry, attitude control, scientific instrumentation, communication, etc.
History
The first published mathematical study of the possibility of an artificial satellite was Newton's cannonball, a thought experiment in A Treatise of the System of the World by Isaac Newton. The first fictional depiction of a satellite being launched into orbit was a short story by Edward Everett Hale, The Brick Moon. The idea surfaced again in Jules Verne's The Begum's Fortune.In 1903, Konstantin Tsiolkovsky published Exploring Space Using Jet Propulsion Devices, which is the first academic treatise on the use of rocketry to launch spacecraft. He calculated the orbital speed required for a minimal orbit, and that a multi-stage rocket fueled by liquid propellants could achieve this.
In 1928, Herman Potočnik published his sole book, The Problem of Space Travel – The Rocket Motor. He described the use of orbiting spacecraft for observation of the ground and described how the special conditions of space could be useful for scientific experiments.
In a 1945 Wireless World article, the English science fiction writer Arthur C. Clarke described in detail 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 that "A satellite vehicle with appropriate instrumentation can be expected to be one of 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 February 1954 Project RAND released "Scientific Uses for a Satellite Vehicle," written 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.
In the context of activities planned for the International Geophysical Year, 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 Soviets announced that they intended to launch a satellite by the fall of 1957.
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 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.
Sputnik 2 was launched on 3 November 1957 and carried the first living passenger into orbit, a dog named Laika.
In early 1955, following pressure by the American Rocket Society, the National Science Foundation, and the International Geophysical Year, the Army and Navy were working 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.
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.
Early satellites were constructed 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 communication satellite launched in 1972.
Currently the largest artificial satellite ever is the International Space Station.
Tracking
Satellites can be tracked from Earth stations and also from other satellites.Space Surveillance Network
The United States Space Surveillance Network, a division of the United States Strategic Command, has been tracking objects in Earth's orbit since 1957 when the Soviet Union opened the Space Age with the launch of Sputnik I. Since then, the SSN has tracked more than 26,000 objects. The SSN currently tracks more than 8,000-artificial orbiting objects. The rest have re-entered Earth's atmosphere and disintegrated, or survived re-entry and impacted the Earth. The SSN tracks objects that are 10 centimeters in diameter or larger; those now orbiting Earth range from satellites weighing several tons to pieces of spent rocket bodies weighing only 10 pounds. About seven percent are operational satellites, the rest are space debris. The United States Strategic Command is primarily interested in the active satellites, but also tracks space debris which upon reentry might otherwise be mistaken for incoming missiles.Services
There are three basic categories of satellite services:Fixed satellite services
handle hundreds of billions of voice, data, and video transmission tasks across all countries and continents between certain points on the Earth's surface.Mobile satellite systems
Mobile satellite systems help connect remote regions, vehicles, ships, people and aircraft to other parts of the world and/or other mobile or stationary communications units, in addition to serving as navigation systems.Scientific research satellites (commercial and noncommercial)
Scientific research satellites provide meteorological information, land survey data, Amateur Radio, and other different scientific research applications such as earth science, marine science, and atmospheric research.Types
- Astronomical satellites are satellites used for observation of distant planets, galaxies, and other outer space objects.
- Biosatellites are satellites designed to carry living organisms, generally for scientific experimentation.
- Communication satellites are satellites stationed in space for the purpose of telecommunications. Modern communications satellites typically use geosynchronous orbits, Molniya orbits or Low Earth orbits.
- Earth observation satellites are satellites intended for non-military uses such as environmental monitoring, meteorology, map making etc.
- Navigational satellites are satellites which use radio time signals transmitted to enable mobile receivers on the ground to determine their exact location. The relatively clear line of sight between 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.
- Killer satellites are satellites that are designed to destroy enemy warheads, satellites, and other space assets.
- Crewed spacecraft are large satellites able to put humans into an orbit, and return them to Earth. Spacecraft including spaceplanes of reusable systems have major propulsion or landing facilities. They can be used as transport to and from the orbital stations.
- Miniaturized satellites are satellites of unusually low masses and small sizes. New classifications are used to categorize these satellites: minisatellite, microsatellite, nanosatellite.
- Reconnaissance satellites are Earth observation satellite or communications satellite deployed for military or intelligence applications. Very little is known about the full power of these satellites, as governments who operate them usually keep information pertaining to their reconnaissance satellites classified.
- Recovery satellites are satellites that provide a recovery of reconnaissance, biological, space-production and other payloads from orbit to Earth.
- Space-based solar power satellites are proposed satellites that would collect energy from sunlight and transmit it for use on Earth or other places.
- Space stations are artificial orbital structures that are designed for human beings to live on in outer space. A space station is distinguished from other crewed spacecraft by its lack of major propulsion or landing facilities. Space stations are designed for medium-term living in orbit, for periods of weeks, months, or even years.
- Tether satellites are satellites which are connected to another satellite by a thin cable called a tether.
- Weather satellites are primarily used to monitor Earth's weather and climate.
Orbits
The commonly used altitude classifications of geocentric orbit are Low Earth orbit, Medium Earth orbit and High Earth orbit. Low Earth orbit is any orbit below 2,000 km. Medium Earth orbit is any orbit between 2,000 and 35,786 km. High Earth orbit is any orbit higher than 35,786 km.
Centric classifications
- Galactocentric orbit: An orbit around the centre of a galaxy. The Sun follows this type of orbit about the galactic centre of the Milky Way.
- Geocentric orbit: An orbit around the planet Earth, such as the Moon or artificial satellites. Currently there are over 2218 artificial satellites orbiting the Earth.
- Heliocentric orbit: An orbit around the Sun. In our Solar System, all planets, comets, and asteroids are in such orbits, as are many artificial satellites and pieces of space debris. Moons by contrast are not in a heliocentric orbit but rather orbit their parent planet.
- Areocentric orbit: An orbit around the planet Mars, such as by moons or artificial satellites.
Altitude classifications
- Low Earth orbit : Geocentric orbits ranging in altitude from 180 km –
- Medium Earth orbit : Geocentric orbits ranging in altitude from –. Also known as an intermediate circular orbit.
- Geosynchronous orbit : Geocentric circular orbit with an altitude of. The period of the orbit equals one sidereal day, coinciding with the rotation period of the Earth. The speed is approximately.
- High Earth orbit : Geocentric orbits above the altitude of geosynchronous orbit.
Inclination classifications
- Inclined orbit: An orbit whose inclination in reference to the equatorial plane is not zero degrees.
- * Polar orbit: An orbit that passes above or nearly above both poles of the planet on each revolution. Therefore, it has an inclination of 90 degrees.
- * Polar sun synchronous orbit: A nearly polar orbit that passes the equator at the same local time on every pass. Useful for image taking satellites because shadows will be nearly the same on every pass.
Eccentricity classifications
- Circular orbit: An orbit that has an eccentricity of 0 and whose path traces a circle.
- * Hohmann transfer orbit: An orbit that moves a spacecraft from one approximately circular orbit, usually the orbit of a planet, to another, using two engine impulses. The perihelion of the transfer orbit is at the same distance from the Sun as the radius of one planet's orbit, and the aphelion is at the other. The two rocket burns change the spacecraft's path from one circular orbit to the transfer orbit, and later to the other circular orbit. This maneuver was named after Walter Hohmann.
- Elliptic orbit: An orbit with an eccentricity greater than 0 and less than 1 whose orbit traces the path of an ellipse.
- * Geosynchronous transfer orbit: An elliptic orbit where the perigee is at the altitude of a Low Earth orbit and the apogee at the altitude of a geosynchronous orbit.
- * Geostationary transfer orbit: An elliptic orbit where the perigee is at the altitude of a Low Earth orbit and the apogee at the altitude of a geostationary orbit.
- * Molniya orbit: A highly elliptic orbit with inclination of 63.4° and orbital period of half of a sidereal day. Such a satellite spends most of its time over two designated areas of the planet.
- * Tundra orbit: A highly elliptic orbit with inclination of 63.4° and orbital period of one sidereal day. Such a satellite spends most of its time over a single designated area of the planet.
Synchronous classifications
- Synchronous orbit: An orbit where the satellite has an orbital period equal to the average rotational period of the body being orbited and in the same direction of rotation as that body. To a ground observer such a satellite would trace an analemma in the sky.
- Semi-synchronous orbit : An orbit with an altitude of approximately and an orbital period equal to one-half of the average rotational period of the body being orbited
- Geosynchronous orbit : Orbits with an altitude of approximately. Such a satellite would trace an analemma in the sky.
- *Geostationary orbit : A geosynchronous orbit with an inclination of zero. To an observer on the ground this satellite would appear as a fixed point in the sky.
- ** Clarke orbit: Another name for a geostationary orbit. Named after scientist and writer Arthur C. Clarke.
- * Supersynchronous orbit: A disposal / storage orbit above GSO/GEO. Satellites will drift west. Also a synonym for Disposal orbit.
- * Subsynchronous orbit: A drift orbit close to but below GSO/GEO. Satellites will drift east.
- * Graveyard orbit: An orbit a few hundred kilometers above geosynchronous that satellites are moved into at the end of their operation.
- **Disposal orbit: A synonym for graveyard orbit.
- ** Junk orbit: A synonym for graveyard orbit.
- Areosynchronous orbit: A synchronous orbit around the planet Mars with an orbital period equal in length to Mars' sidereal day, 24.6229 hours.
- Areostationary orbit : A circular areosynchronous orbit on the equatorial plane and about 17000 km above the surface. To an observer on the ground this satellite would appear as a fixed point in the sky.
- Heliosynchronous orbit: A heliocentric orbit about the Sun where the satellite's orbital period matches the Sun's period of rotation. These orbits occur at a radius of 24,360 Gm around the Sun, a little less than half of the orbital radius of Mercury.
Special classifications
- Sun-synchronous orbit: An orbit which combines altitude and inclination in such a way that the satellite passes over any given point of the planets' surface at the same local solar time. Such an orbit can place a satellite in constant sunlight and is useful for imaging, spy, and weather satellites.
- Moon orbit: The orbital characteristics of Earth's Moon. Average altitude of, elliptical–inclined orbit.
Pseudo-orbit classifications
- Horseshoe orbit: An orbit that appears to a ground observer to be orbiting a certain planet but is actually in co-orbit with the planet. See asteroids 3753 and 2002 AA29.
- Suborbital spaceflight: A maneuver where a spacecraft approaches the height of orbit but lacks the velocity to sustain it.
- Lunar transfer orbit
- Prograde orbit: An orbit with an inclination of less than 90°. Or rather, an orbit that is in the same direction as the rotation of the primary.
- Retrograde orbit: An orbit with an inclination of more than 90°. Or rather, an orbit counter to the direction of rotation of the planet. Apart from those in sun-synchronous orbit, few satellites are launched into retrograde orbit because the quantity of fuel required to launch them is much greater than for a prograde orbit. This is because when the rocket starts out on the ground, it already has an eastward component of velocity equal to the rotational velocity of the planet at its launch latitude.
- Halo orbit and Lissajous orbit: Orbits "around" Lagrangian points.
Subsystems
Spacecraft bus or service module
The bus module consists of the following subsystems:Structural subsystem
The structural subsystem provides the mechanical base structure with adequate stiffness to withstand stress and vibrations experienced during launch, maintain structural integrity and stability while on station in orbit, and shields the satellite from extreme temperature changes and micro-meteorite damage.Telemetry subsystem
The telemetry subsystem monitors the on-board equipment operations, transmits equipment operation data to the earth control station, and receives the earth control station's commands to perform equipment operation adjustments.Power subsystem
The power subsystem consists of solar panels to convert solar energy into electrical power, regulation and distribution functions, and batteries that store power and supply the satellite when it passes into the Earth's shadow. Nuclear power sources have also been used in several successful satellite programs including the Nimbus program.Thermal control subsystem
The thermal control subsystem helps protect electronic equipment from extreme temperatures due to intense sunlight or the lack of sun exposure on different sides of the satellite's bodyAttitude and orbit control subsystem
The attitude and orbit control subsystem consists of sensors to measure vehicle orientation, control laws embedded in the flight software, and actuators. These apply the torques and forces needed to re-orient the vehicle to a desired attitude, keep the satellite in the correct orbital position, and keep antennas pointed in the right directions.Communication payload
The second major module is the communication payload, which is made up of transponders. A transponder is capable of :- Receiving uplinked radio signals from earth satellite transmission stations.
- Amplifying received radio signals
- Sorting the input signals and directing the output signals through input/output signal multiplexers to the proper downlink antennas for retransmission to earth satellite receiving stations.
End of life
Instead of being de-orbited, most satellites are either left in their current orbit or moved to a graveyard orbit. 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. In cases of uncontrolled de-orbiting, the major variable is the solar flux, and the minor variables the components and form factors of the satellite itself, and the gravitational perturbations generated by the Sun and the Moon. The nominal breakup altitude due to aerodynamic forces and temperatures is 78 km, with a range between 72 and 84 km. Solar panels, however, are destroyed before any other component at altitudes between 90 and 95 km.
Launch-capable countries
This list includes countries with an independent capability to place satellites in orbit, including production of the necessary launch vehicle. Note: many more countries have the capability to design and build satellites but are unable to launch them, instead relying on foreign launch services. This list does not consider those numerous countries, but only lists those capable of launching satellites indigenously, and the date this capability was first demonstrated. The list does not include the European Space Agency, a multi-national state organization, nor private consortiums.| Order | Country | Date of first launch | Rocket | Satellite |
| 1 | Soviet Union | 4 October 1957 | Sputnik-PS | Sputnik 1 |
| 2 | United States | 1 February 1958 | Juno I | Explorer 1 |
| 3 | France | 26 November 1965 | Diamant-A | Astérix |
| 4 | Japan | 11 February 1970 | Lambda-4S | Ohsumi |
| 5 | China | 24 April 1970 | Long March 1 | Dong Fang Hong I |
| 6 | United Kingdom | 28 October 1971 | Black Arrow | Prospero |
| 7 | India | 18 July 1980 | SLV | Rohini D1 |
| 8 | Israel | 19 September 1988 | Shavit | Ofeq 1 |
| – | Russia | 21 January 1992 | Soyuz-U | Kosmos 2175 |
| – | Ukraine | 13 July 1992 | Tsyklon-3 | Strela |
| 9 | Iran | 2 February 2009 | Safir-1 | Omid |
| 10 | North Korea | 12 December 2012 | Unha-3 | Kwangmyŏngsŏng-3 Unit 2 |
| 11 | South Korea | 30 January 2013 | Naro-1 | STSAT-2C |
| 12 | New Zealand | 12 November 2018 | Electron | CubeSat |
Attempted first launches
- The United States tried in 1957 to launch the first satellite using its own launcher before successfully completing a launch in 1958.
- Japan tried four times in 1966–1969 to launch a satellite with its own launcher before successfully completing a launch in 1970.
- China tried in 1969 to launch the first satellite using its own launcher before successfully completing a launch in 1970.
- India, after launching its first national satellite using a foreign launcher in 1975, tried in 1979 to launch the first satellite using its own launcher before succeeding in 1980.
- Iraq have claimed an orbital launch of a warhead in 1989, but this claim was later disproved.
- Brazil, after launching its first national satellite using a foreign launcher in 1985, tried to launch a satellite using its own VLS 1 launcher three times in 1997, 1999, and 2003, but all attempts were unsuccessful.
- North Korea claimed a launch of Kwangmyŏngsŏng-1 and Kwangmyŏngsŏng-2 satellites in 1998 and 2009, but U.S., Russian and other officials and weapons experts later reported that the rockets failed to send a satellite into orbit, if that was the goal. The United States, Japan and South Korea believe this was actually a ballistic missile test, which was a claim also made after North Korea's 1998 satellite launch, and later rejected. The first launch of Kwangmyŏngsŏng-3 was unsuccessful, a fact publicly recognized by the DPRK. However, the December 2012 launch of the "second version" of Kwangmyŏngsŏng-3 was successful, putting the DPRK's first confirmed satellite into orbit.
- South Korea, after launching their first national satellite by foreign launcher in 1992, unsuccessfully tried to launch its own launcher, the KSLV -1, in 2009 and 2010 until success was achieved in 2013 by Naro-3.
- The First European multi-national state organization ELDO tried to make the orbital launches at Europa I and Europa II rockets in 1968–1970 and 1971 but stopped operation after failures.
Other notes
- Russia and the Ukraine were parts of the Soviet Union and thus inherited their launch capability without the need to develop it indigenously. Through the Soviet Union they are also on the number one position in this list of accomplishments.
- France, the United Kingdom, and Ukraine launched their first satellites by own launchers from foreign spaceports.
- Some countries such as South Africa, Spain, Italy, Germany, Canada, Australia, Argentina, Egypt and private companies such as OTRAG, have developed their own launchers, but have not had a successful launch.
- Only twelve, countries from the list below and one regional organization have independently launched satellites on their own indigenously developed launch vehicles.
- Several other countries, including Brazil, Argentina, Pakistan, Romania, Taiwan, Indonesia, Australia, Malaysia, Turkey and Switzerland are at various stages of development of their own small-scale launcher capabilities.
Launch capable private entities
First satellites of countries
| Country | Year of first launch | First satellite | Operational payloads in orbit as of April 2020 |
| Soviet Union | 1957 | Sputnik 1 | 1524 |
| United States | 1958 | Explorer 1 | 1914 |
| China | 1970 | Dong Fang Hong I | 391 |
| Japan | 1970 | Ohsumi | 181 |
| India | 1975 | Aryabhata | 96 |
| France | 1965 | Astérix | 73 |
| Germany | 1969 | Azur | 67 |
| Canada | 1962 | Alouette 1 | 54 |
| United Kingdom | 1962 | Ariel 1 | 54 |
| Italy | 1964 | San Marco 1 | 29 |
| South Korea | 1992 | Kitsat A | 23 |
| Spain | 1974 | Intasat | 27 |
| Australia | 1967 | WRESAT | 22 |
| Brazil | 1985 | Brasilsat-A1 | 21 |
| Argentina | 1990 | Lusat | 20 |
| Israel | 1988 | Ofeq 1 | 20 |
| Indonesia | 1976 | Palapa A1 | 18 |
| Turkey | 1994 | Turksat 1B | 13 |
| Saudi Arabia | 1985 | Arabsat-1A | 15 |
| Mexico | 1985 | Morelos 1 | 13 |
| Sweden | 1986 | Viking | 11 |
| Singapore | 1998 | ST-1 | 11 |
| Netherlands | 1974 | ANS | 8 |
| Czechoslovakia | 1978 | Magion 1 | 2 |
| Bulgaria | 1981 | Intercosmos Bulgaria 1300 | 2 |
| Luxembourg | 1988 | Astra 1A | 4 |
| Pakistan | 1990 | Badr-1 | 6 |
| Portugal | 1993 | PoSAT-1 | 2 |
| Thailand | 1993 | Thaicom 1 | 10 |
| Czech Republic | 1995 | Magion 4 | 3 |
| Ukraine | 1995 | Sich-1 | 6 |
| Malaysia | 1996 | MEASAT | 7 |
| Norway | 1997 | Thor 2 | 9 |
| Philippines | 1997 | Mabuhay 1 | 2 |
| Egypt | 1998 | Nilesat 101 | 5 |
| Chile | 1998 | FASat-Bravo | 3 |
| Denmark | 1999 | Ørsted | 9 |
| South Africa | 1999 | SUNSAT | 6 |
| United Arab Emirates | 2000 | Thuraya 1 | 9 |
| Morocco | 2001 | Maroc-Tubsat | 1 |
| Belgium | 2001 | PROBA-1 | 0 |
| Tonga | 2002 | Esiafi 1 | 0 |
| Algeria | 2002 | Alsat 1 | 6 |
| Greece | 2003 | Hellas Sat 2 | 4 |
| Cyprus | 2003 | Hellas Sat 2 | 0 |
| Nigeria | 2003 | Nigeriasat 1 | 6 |
| Iran | 2005 | Sina-1 | 1 |
| Kazakhstan | 2006 | KazSat 1 | 6 |
| Colombia | 2007 | Libertad 1 | 0 |
| Mauritius | 2007 | Rascom-QAF 1 | 0 |
| Vietnam | 2008 | Vinasat-1 | 3 |
| Venezuela | 2008 | Venesat-1 | 3 |
| Switzerland | 2009 | SwissCube-1 | 0 |
| Isle of Man | 2011 | ViaSat-1 | 1 |
| Poland | 2012 | PW-Sat | 4 |
| Hungary | 2012 | MaSat-1 | 0 |
| Sri Lanka | 2012 | SupremeSAT-I | 1 |
| Romania | 2012 | Goliat | 0 |
| Belarus | 2012 | BKA | 2 |
| North Korea | 2012 | Kwangmyŏngsŏng-3 Unit 2 | 2 |
| Azerbaijan | 2013 | Azerspace | 1 |
| Austria | 2013 | TUGSAT-1/UniBRITE | 0 |
| Bermuda | 2013 | Bermudasat 1 | 0 |
| Ecuador | 2013 | NEE-01 Pegaso | 2 |
| Estonia | 2013 | ESTCube-1 | 1 |
| Jersey | 2013 | O3b-1, −2, −3, −4 | 0 |
| Qatar | 2013 | Es'hailSat1 | 0 |
| Peru | 2013 | PUCPSAT-1 | 2 |
| Bolivia | 2013 | TKSat-1 | 1 |
| Lithuania | 2014 | LituanicaSAT-1 and LitSat-1 | 1 |
| Uruguay | 2014 | Antelsat | 1 |
| Iraq | 2014 | Tigrisat | 0 |
| Turkmenistan | 2015 | TurkmenAlem52E/MonacoSAT | 1 |
| Laos | 2015 | Laosat-1 | 1 |
| Finland | 2017 | Aalto-2 | 1 |
| Bangladesh | 2017 | BRAC Onnesha | 2 |
| Ghana | 2017 | GhanaSat-1 | 1 |
| Mongolia | 2017 | Mazaalai | 1 |
| Latvia | 2017 | Venta-1 | 1 |
| Slovakia | 2017 | skCUBE | 1 |
| Asgardia | 2017 | Asgardia-1 | 1 |
| Angola | 2017 | AngoSat 1 | 1 |
| New Zealand | 2018 | Humanity Star | 1 |
| Bangladesh | 2018 | Bangabandhu-1 | 1 |
| Costa Rica | 2018 | Proyecto Irazú | 1 |
| Kenya | 2018 | 1KUNS-PF | 1 |
| Bhutan | 2018 | BHUTAN-1 | 1 |
| Jordan | 2018 | JY1-SAT | 1 |
| Nepal | 2019 | NepaliSat-1 | 1 |
| Rwanda | 2019 | RWASat-1 | 1 |
| Sudan | 2019 | SRSS-1 | 1 |
| Ethiopia | 2019 | ETRSS-1 | 1 |
| Guatemala | 2020 | Quetzal-1 | 1 |
While Canada 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, who launched 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 launched on 15 December 1964 on a U.S. Scout rocket from Wallops Island with an Italian launch team trained by NASA. By similar occasions, almost all further first national satellites was launched by foreign rockets.
Attempted first satellites
- United States tried unsuccessfully to launch its first satellite in 1957; they were successful in 1958.
- China tried unsuccessfully to launch its first satellite in 1969; they were successful in 1970.
- Iraq under Saddam Hussein fulfilled in 1989 an unconfirmed launch of warhead on orbit by developed Iraqi vehicle that intended to put later the 75 kg first national satellite Al-Ta’ir, also developed.
- Chile tried unsuccessfully in 1995 to launch its first satellite FASat-Alfa by foreign rocket; in 1998 they were successful.†
- North Korea has tried in 1998, 2009, 2012 to launch satellites, first successful launch on 12 December 2012.
- Libya since 1996 developed its own national Libsat satellite project with the goal of providing telecommunication and remote sensing services that was postponed after the fall of Gaddafi.
- Belarus tried unsuccessfully in 2006 to launch its first satellite BelKA by foreign rocket.†
Planned first satellites
- Afghanistan announced in April 2012 that it is planning to launch its first communications satellite to the orbital slot it has been awarded. The satellite Afghansat 1 was expected to be obtained by a Eutelsat commercial company in 2014.
- Armenia in 2012 founded Armcosmos company and announced an intention to have the first telecommunication satellite ArmSat. The investments estimates as $250 million and country selecting the contractor for building within 4 years the satellite amongst Russia, China and Canada
- Cambodia's Royal Group plans to purchase for $250–350 million and launch in the beginning of 2013 the telecommunication satellite.
- Cayman Islands's Global IP Cayman private company plans to launch GiSAT-1 geostationary communications satellite in 2018.
- Democratic Republic of Congo ordered at November 2012 in China and Great Wall Industry Corporation ) the first telecommunication satellite CongoSat-1 which will be built on DFH-4 satellite bus platform and will be launched in China till the end of 2015.
- Croatia has a goal to construct a satellite by 2013–2014. Launch into Earth orbit would be done by a foreign provider.
- Ireland's team of Dublin Institute of Technology intends to launch the first Irish satellite within European University program CubeSat QB50.
- Republic of Moldova's first remote sensing satellite plans to start in 2013 by Space centre at national Technical University.
- Monaco's first satellite OSM-1 Cicero planned to launch in 2020.
- Myanmar plans to purchase for $200 million their own telecommunication satellite.
- Nicaragua ordered for $254 million at November 2013 in China the first telecommunication satellite Nicasat-1, that planning to launch in China at 2016.
- Paraguay under new Agencia Espacial del Paraguay –- AEP airspace agency plans first Eart observation satellite.
- Serbia's first satellite Tesla-1 was designed, developed and assembled by nongovernmental organisations in 2009 but still remains unlaunched.
- Slovenia's Earth observation microsatellite for the Slovenian Centre of Excellence for Space Sciences and Technologies now under development for $2 million since 2010 by University of Toronto Institute for Aerospace Studies – Space Flight Laboratory and planned to launch in 2020.
- Sri Lanka has a goal to construct two satellites beside of rent the national SupremeSAT payload in Chinese satellites. Sri Lankan Telecommunications Regulatory Commission has signed an agreement with Surrey Satellite Technology Ltd to get relevant help and resources. Launch into Earth orbit would be done by a foreign provider.
- Syrian Space Research Center developing CubeSat-like small first national satellite since 2008.
- Tunisia is developing its first satellite, ERPSat01. Consisting of a CubeSat of 1 kg mass, it will be developed by the Sfax School of Engineering. ERPSat satellite is planned to be launched into orbit in 2013.
- Uzbekistan's State Space Research Agency announced in 2001 about intention of launch in 2002 first remote sensing satellite. Later in 2004 was stated that two satellites will be built by Russia for $60–70 million each
Attacks on satellites
For testing purposes, satellites in low earth orbit have been destroyed by ballistic missiles launched from earth. Russia, the United States, China and India have demonstrated the ability to eliminate satellites. In 2007 the Chinese military shot down an aging weather satellite, followed by the US Navy shooting down a defunct spy satellite in February 2008. On 27 March 2019 India shot down a live test satellite at 300 km altitude in 3 minutes. India became the fourth country to having capability to destroy live satellite.
Jamming
Due to the low received signal strength of satellite transmissions, they are prone to jamming by land-based transmitters. Such jamming is limited to the geographical area within the transmitter's range. GPS satellites are potential targets for jamming, but satellite phone and television signals have also been subjected to jamming.Also, it is very easy to transmit a carrier radio signal to a geostationary satellite and thus interfere with the legitimate uses of the satellite's transponder. It is common for Earth stations to transmit at the wrong time or on the wrong frequency in commercial satellite space, and dual-illuminate the transponder, rendering the frequency unusable. Satellite operators now have sophisticated monitoring that enables them to pinpoint the source of any carrier and manage the transponder space effectively.
Earth observation
During the last five decades, space agencies have sent thousands of space crafts, space capsules, or satellites to the universe. In fact, weather forecasters make predictions on the weather and natural calamities based on observations from these satellites.The National Aeronautics and Space Administration requested the National Academies to publish a report entitled, Earth Observations from Space; The First 50 Years of Scientific Achievements in 2008. It described how the capability to view the whole globe simultaneously from satellite observations revolutionized studies about the planet Earth. This development brought about a new age of combined Earth sciences. The National Academies report concluded that continuing Earth observations from the galaxy are necessary to resolve scientific and social challenges in the future.
NASA
The NASA introduced an Earth Observing System composed of several satellites, science component, and data system described as the Earth Observing System Data and Information System. It disseminates numerous science data products as well as services designed for interdisciplinary education. EOSDIS data can be accessed online and accessed through File Transfer Protocol and Hyper Text Transfer Protocol Secure. Scientists and researchers perform EOSDIS science operations within a distributed platform of multiple interconnected nodes or Science Investigator-led Processing Systems and discipline-specific Distributed Active Archive Centers.ESA
The European Space Agency have been operating Earth Observation satellites since the launch of Meteosat 1 in November 1977. ESA currently has plans to launch a satellite equipped with an artificial intelligence processor that will allow the spacecraft to make decisions on images to capture and data to transmit to the Earth. BrainSat will use the Intel Myriad X vision processing unit. The launching will be scheduled in 2019. ESA director for Earth Observation Programs Josef Aschbacher made the announcement during the PhiWeek in November 2018. This is the five-day meet that focused on the future of Earth observation. The conference was held at the ESA Center for Earth Observation in Frascati, Italy. ESA also launched the PhiLab, referring to the future-focused team that works to harness the potentials of AI and other disruptive innovations. Meanwhile, the ESA also announced that it expects to commence the qualification flight of the Space Rider space plane in 2021. This will come after several demonstration missions. Space Rider is the sequel of the Agency's Intermediate Experimental vehicle which was launched in 2015. It has the capacity payload of 800 kilograms for orbital missions that will last a maximum of two months.SpaceX
SpaceX was scheduled to launch a multiple satellite mission on 28 November 2018 from the United States Vandenberg Air Force Base after an initial 19 November schedule. The launch is expected to be visible once the rocket heads toward the south into an Earth observation trajectory traveling over the poles. However, the second supposed launched was delayed again because of poor weather conditions and the actual launch occurred on 3 December 2018. The mission is known as the SSO-A Smallsat Express was executed by Spaceflight, a rideshare and mission management provider based in Seattle, Wash. The launch was a landmark for Elon Musk, founder of SpaceX which had 19 rocket launches in 2018 alone. The estimated cost of this Falcon 9 rocket is approximately $62 million. The rocket has 60 satellites with each one going separate ways. On April 22, 2020, SpaceX launched their 7th constellation of 60 satellites, boosting the StarLink constellation to a total of 420 satellites in low Earth orbit.Amazon and Lockheed
Amazon Web Services and Lockheed Martin entered into a strategic partnership for the purpose of integrating the AWS ground station service with Lockheed's verge antenna network. These two corporations aim to merge these highly-capable systems that will provide clients with robust satellite uplinks and downlinks. Through these systems, users can incorporate satellite data with various AWS services which include computing, storage, analytics, and machine-learning.Pollution and regulation
Generally liability has been covered by the Liability Convention.Issues like space debris, radio and light pollution are increasing in magnitude and at the same time lack progress in national or international regulation.
With future increase in numbers of satellite constellations, like SpaceX Starlink, it is feared especially by the astronomical community, such as the IAU, that orbital pollution will increase significantly. Some notable satellite failures that polluted and dispersed radioactive materials are Kosmos 954, Kosmos 1402 and the Transit 5-BN-3.