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imported>Carl Jantzen
(Direct Copy from Wikipedia dated 17:15, 4 July 2007)
 
imported>Carl Jantzen
(Deleted a lot of stuff. I just wanted to include a basic definition for a relatively important topic.)
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[[Image:ERS 2.jpg|thumb|right|300 px|An Earth observation satellite, [[ERS 2]]]]
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{{otheruses}}
In the context of [[spaceflight]], '''satellites''' are objects which have been placed into [[orbit]] by human endeavor. They are sometimes called '''artificial satellites''' to distinguish them from [[natural satellite]]s such as the [[Moon]].
In the context of [[spaceflight]], '''satellites''' are objects which have been placed into [[orbit]] by human endeavor. They are sometimes called '''artificial satellites''' to distinguish them from [[natural satellite]]s such as the [[Moon]].


==Early theoretical work on artificial satellites ==
==History==
The first known fictional depiction of a satellite being launched into orbit is a [[short story]] by [[Edward Everett Hale]], ''[[The Brick Moon]]''. The story was serialized in ''[[The Atlantic Monthly]]'', starting in 1869.<ref>
{{cite web | url = http://www.gutenberg.org/etext/1633 | title = The Brick Moon and Other Stories by Edward Everett Hale | publisher = Project Gutenberg}}</ref><ref>
{{cite web | url = http://cdl.library.cornell.edu/cgi-bin/moa/pageviewer?frames=1&cite=http%3A%2F%2Fcdl.library.cornell.edu%2Fcgi-bin%2Fmoa%2Fmoa-cgi%3Fnotisid%3DABK2934-0024-50&coll=moa&view=50&root=%2Fmoa%2Fatla%2Fatla0024%2F&tif=00005.TIF  | title = Contents - The Atlantic monthly. Volume 24, Issue 141 | publisher = Cornell University Library}}</ref> The idea surfaces again in [[Jules Verne]]'s [[The Begum's Millions]] ([[1879]]).
 
In 1903 [[Konstantin Tsiolkovsky]] (1857&ndash;1935) published ''Исследование мировых пространств реактивными приборами'' (''The Exploration of Cosmic Space by Means of Reaction 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]] around the Earth at 8&nbsp;km/second, and that a [[multi-stage rocket]] fueled by liquid [[propellant]]s could be used to achieve this. He proposed the use of [[liquid hydrogen]] and [[liquid oxygen]], though other combinations can be used. During his lifetime he published over 500 works on space travel and related subjects, including science fiction novels. Among his works are designs for rockets with steering thrusters, multi-stage boosters, space stations, airlocks for exiting a spaceship into the vacuum of space, and closed cycle biological systems to provide food and oxygen for space colonies. He also delved into theories of heavier-than-air flying machines, independently working through many of the same calculations that the [[Wright brothers]] were performing at about the same time.
 
In 1928 [[Herman Potočnik]] (1898&ndash;1929) published his sole book, ''Das Problem der Befahrung des Weltraums - der Raketen-Motor'' (''The Problem of Space Travel - The Rocket Motor''), a plan for a breakthrough into space and a permanent human presence there. He conceived of a space station in detail and calculated its [[geostationary orbit]]. He described the use of orbiting spacecraft for detailed peaceful and military observation of the ground and described how the special conditions of space could be useful for scientific experiments. 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.
 
In a 1945 ''[[Wireless World]]'' article the English science fiction writer [[Arthur C. Clarke]] (b. 1917) described in detail the possible use of [[communications satellite]]s for mass communications.<ref>facsimile at http://www.lsi.usp.br/~rbianchi/clarke/ACC.ETRelaysFull.html</ref> 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.
 
== History of artificial satellites ==
{{see also | Space Race}}
 
; Soviet Union
The first artificial satellite was [[Sputnik 1]], launched by the [[Soviet Union]] on [[4 October]] [[1957]]. This triggered the [[Space Race]] between the Soviet Union and the [[United States]].
The first artificial satellite was [[Sputnik 1]], launched by the [[Soviet Union]] on [[4 October]] [[1957]]. This triggered the [[Space Race]] between the Soviet Union and the [[United States]].
; United States
In May, 1946, [[Project RAND]] had 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 the most potent scientific tools of the Twentieth Century.<ref>
{{cite web | url = http://www.rand.org/pubs/special_memoranda/SM11827/index.html | title = Preliminary Design of an Experimental World-Circling Spaceship | publisher = [[RAND]]}}</ref>
The [[United States]] had been considering launching [[orbit]]al satellites since 1945 under the [[Bureau of Aeronautics]] of the [[United States Navy]]. The [[United States Air Force|Air Force's]] Project RAND eventually released the above report, but did not believe that the satellite was a potential military [[weapon]]; rather they considered it to be a tool for [[science]], [[politics]], and [[propaganda]]. In 1954, the Secretary of Defense stated, "I know of no American satellite program."
Following pressure by the [[American Rocket Society]], the [[National Science Foundation]], and the [[International Geophysical Year]], military interest picked up and in early 1955 the Air Force and Navy were working on [[Project Orbiter]], which involved using a [[Jupiter-C IRBM|Jupiter C rocket]] to launch a small satellite called [[Explorer 1]] on [[January 31]], [[1958]].
On [[July 29]], [[1955]], the [[White House]] announced that the U.S. intended to launch satellites by the [[spring (season)|spring]] of 1958. This became known as [[Project Vanguard]]. On [[July 31]], the Soviets announced that they intended to launch a satellite by the fall of 1957.
; International
The largest artificial satellite currently orbiting the Earth is the [[International Space Station]].
== Space Surveillance Network ==
The [[United States Space Surveillance Network]] (SSN) has been tracking space objects since 1957 when the Soviets opened the space age with the launch of Sputnik I. Since then, the SSN has tracked more than 26,000 space objects orbiting Earth. The SSN currently tracks more than 8,000 man-made orbiting objects. The rest have re-entered Earth's turbulent atmosphere and disintegrated, or survived re-entry and impacted the Earth. The space objects now orbiting Earth range from satellites weighing several tons to pieces of spent rocket bodies weighing only 10 pounds. About seven percent of the space objects are operational satellites (i.e. - ~560 satellites), the rest are debris. [[USSTRATCOM]] is primarily interested in the active satellites, but also tracks space debris which upon reentry might otherwise be mistaken for incoming missiles. The SSN tracks space objects that are 10 centimeters in diameter (baseball size) or larger.
==Types==
[[Image:Milstar.jpg|thumb|[[MILSTAR]]:A communication satellite]]
*'''[[Anti-satellite weapon|Anti-Satellite weapons]]''', sometimes called "Killer satellites" are satellites designed to destroy "enemy" satellites, other orbital weapons and targets. Some are armed with kinetic rounds, while others use energy and/or particle weapons to destroy satellites, ICBMs, MIRVs. Both the U.S. and the USSR had these satellites. Links discussing "Killer satellites", ASATS (Anti-Satellite satellite) include [http://www.jamesoberg.com/pearl.html USSR Tests ASAT weapon] and [http://www.patricksaviation.com/wiki/F-15_ASAT ASAT Test]. See also [[IMINT]]
*'''[[Astronomical satellite]]s''' are satellites used for observation of distant planets, galaxies, and other outer space objects.
*'''[[Biosatellite]]s''' are satellites designed to carry living organisms, generally for scientific experimentation.
*'''[[Communications satellite]]s''' are satellites stationed in space for the purpose of [[telecommunications]]. Modern communications satellites typically use [[geosynchronous orbit]]s, [[Molniya orbit]]s or [[Low Earth orbit]]s.
*'''[[Miniaturized satellites]]''' are satellites of unusually low weights and small sizes. New classifications are used to categorize these satellites: minisatellite (500&ndash;200&nbsp;kg), microsatellite (below 200&nbsp;kg), nanosatellite (below 10&nbsp;kg).
*'''[[Global Navigation Satellite System|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 metres in real time.
*'''[[Reconnaissance satellite]]s''' are [[Earth observation satellite]] or [[communications satellite]] deployed for [[military]] or [[espionage|intelligence]] applications. Little is known about the full power of these satellites, as governments who operate them usually keep information pertaining to their reconnaissance satellites classified.
*'''[[Earth observation satellite]]s''' are satellites intended for non-military uses such as [[natural environment|environment]]al monitoring, [[meteorology]], [[map making]] etc. (See especially [[Earth Observing System]].)
*'''[[Solar power satellite]]s''' are proposed satellites built in [[high Earth orbit]] that use [[microwave power transmission]] to beam [[solar power]] to very large [[Antenna (electronics)|antennae]] on Earth where it can be used in place of conventional power sources.
*'''[[Space station]]s''' are man-made structures that are designed for [[human|human beings]] to live on in [[outer space]]. A space station is distinguished from other manned [[spacecraft]] by its lack of major [[Spacecraft propulsion|propulsion]] or [[landing]] facilities &mdash; instead, other vehicles are used as transport to and from the station. Space stations are designed for medium-term living in [[orbit]], for periods of [[week]]s, [[month]]s, or even [[year]]s.
*'''[[Weather satellite]]s''' are satellites that primarily are used to monitor [[Earth]]'s [[weather]] and [[climate]].
==Orbit types==
{{main|List of orbits}}
<u>'''Centric Classifications'''</u><br>
:'''[[Galacto-centric Orbit]]''' - An orbit about the center of a [[galaxy]]. [[Earth]]'s [[sun]] follows this type of orbit about the [[galactic center]] of the [[Milky Way]].
:'''[[Heliocentric orbit|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#Moons of the Solar system|Moon]]s by contrast are not in a [[heliocentric orbit]] but rather orbit their parent planet.
:'''[[Geocentric orbit|Geocentric Orbit]]''' - An orbit around the planet [[Earth]], such as the [[Moon]] or [[artificial satellite]]s. Currently there are approximately 2465 artificial satellites orbiting the [[Earth]].
:'''[[Areocentric orbit|Areocentric Orbit]]''' - An orbit around the planet [[Mars]], such as [[Mars moons|moon]]s or [[artificial satellite]]s.
<u>'''Altitude Classifications'''</u><br>
:'''[[Low Earth Orbit]] (LEO)''' - [[Geocentric orbit]]s ranging in altitude from 0 - 2,000 [[km]] (0 - 1,240 [[mile]]s)
:'''[[Medium Earth Orbit]] (MEO)''' - [[Geocentric orbit]]s ranging in altitude from 2,000 [[km]] (1,240 [[mile]]s) - to just below [[geosynchronous orbit]] at 35,786 [[km]] (22,240 [[mile]]s). Also known as an [[intermediate circular orbit]].
:'''[[High Earth Orbit]] (HEO)''' - [[Geocentric orbit]]s above the altitude of [[geosynchronous orbit]] 35,786 [[km]] (22,240 [[mile]]s).
<u>'''Inclination Classifications'''</u><br>
:'''[[Inclined orbit|Inclined Orbit]]''' - An orbit whose [[inclination]] in reference to the [[equatorial plane]] is not 0.
:::'''[[Polar Orbit]]''' - An [[orbit]] that passes above or nearly above both poles of the planet on each revolution. Therefore it has an [[inclination]] of (or very close to) 90 [[degree (angle)|degree]]s.
:::'''[[Polar sun synchronous orbit|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 [[shadow]]s will be the same on every pass.
<u>'''Eccentricity Classifications'''</u><br>
:'''[[Circular Orbit]]''' - An [[orbit]] that has an [[Orbital eccentricity|eccentricity]] of 0 and whose path traces a [[circle]].
::'''[[Hohmann transfer orbit]]''' - An orbital maneuver that moves a [[spacecraft]] from one [[circular orbit]] to another using two engine [[impulse]]s. This maneuver was named after [[Walter Hohmann]].
:'''[[Elliptic orbit|Elliptic Orbit]]''' - An [[orbit]] with an [[Orbital eccentricity|eccentricity]] greater than 0 and less than 1 whose orbit traces the path of an [[ellipse]].
::'''[[Geosynchronous transfer orbit|Geosynchronous Transfer Orbit]]''' - An [[elliptic orbit]] where the [[perigee]] is at the [[altitude]] of a [[Low Earth Orbit]] (LEO) and the [[apogee]] at the [[altitude]] of a [[geosynchronous orbit]].
::'''[[Geosynchronous transfer orbit|Geostationary Transfer Orbit]]''' - An [[elliptic orbit]] where the [[perigee]] is at the [[altitude]] of a [[Low Earth Orbit]] (LEO) and the [[apogee]] at the [[altitude]] of a [[geostationary orbit]].
::'''[[Molniya orbit|Molniya Orbit]]''' - A highly [[elliptic orbit]] with [[inclination]] of 63.4° and [[orbital period]] of ½ of a [[sidereal day]] (roughly 12 hours). Such a satellite spends most of its time over a designated area of the [[planet]].
::'''[[Tundra orbit|Tundra Orbit]]''' - A highly [[elliptic orbit]] with [[inclination]] of 63.4° and [[orbital period]] of one [[sidereal day]] (roughly 24 hours). Such a satellite spends most of its time over a designated area of the [[planet]].
:'''[[Hyperbolic orbit]]''' - An [[orbit]] with the eccentricity greater than 1. Such an orbit also has a [[velocity]] in excess of the [[escape velocity]] and as such, will escape the gravitational pull of the [[planet]] and continue to travel [[infinitely]].
:'''[[Parabolic Orbit]]''' - An [[orbit]] with the eccentricity equal to 1. Such an orbit also has a [[velocity]] equal to the [[escape velocity]] and therefore will escape the gravitational pull of the [[planet]] and travel until its [[velocity]] [[Relative motion#Relative motion|relative]] to the [[planet]] is 0. If the speed of such an orbit is increased it will become a [[hyperbolic orbit]].
::'''[[Escape orbit|Escape Orbit]] (EO)''' - A high-speed [[parabolic orbit]] where the object has [[escape velocity]] and is moving away from the [[planet]].
::'''[[Capture orbit|Capture Orbit]]''' - A high-speed [[parabolic orbit]] where the object has [[escape velocity]] and is moving toward the [[planet]].
<u>'''Synchronous Classifications'''</u><br>
:'''[[Synchronous orbit|Synchronous Orbit]]''' - An orbit where the satellite has an [[orbital period]] equal to the average [[rotational period]] (earth's is: 23 [[hour]]s, 56 [[minute]]s, 4.091 [[second]]s) 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]] (figure 8) in the sky.
:'''[[Semi-synchronous orbit|Semi-Synchronous Orbit]] (SSO)''' - An [[orbit]] with an [[altitude]] of approximately 20,200 km (12544.2 miles) and an [[orbital period]] of approximately 12 hours
:'''[[Geosynchronous Orbit]] (GEO)''' - Orbits with an altitude of approximately 35,786 km (22,240 miles). Such a satellite would trace an [[analemma]] (figure 8) in the sky.
:::'''[[Geostationary orbit]] (GSO)''': 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  the 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|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|Junk Orbit]]''' - A [[synonym]] for [[graveyard orbit]].
:'''[[Areosynchronous 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|Areostationary Orbit]] (ASO)''' - A [[circular]] [[areosynchronous orbit]] on the [[equatorial plane]] and about 17,000 [[km]](10557 [[mile]]s)  above the surface. To an observer on the ground this satellite would appear as a fixed point in the sky.
:'''[[Heliosynchronous orbit|Heliosynchronous Orbit]]''' - An [[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 [[gigametre|Gm]] (0.1628 [[AU]]) around the [[Sun]], a little less than half of the [[orbital radius]] of [[Mercury (planet)|Mercury]].
<u>'''Special Classifications'''</u><br>
:'''[[Sun-synchronous orbit|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]]'s surface at the same local [[solar time]]. Such an orbit can place a satellite in constant sunlight and is useful for [[imaging]], [[spy satellite|spy]], and [[weather satellite]]s.
:'''[[Moon orbit|Moon Orbit]]''' - The [[Orbital parameters|orbital characteristics]] of [[earth]]'s [[moon]]. Average [[altitude]] of 384,403 kilometres (238,857 mi), [[elliptical orbit|elliptical]]-[[inclined orbit]].
<u>'''Pseudo-Orbit Classifications'''</u><br>
:'''[[Horseshoe orbit|Horseshoe Orbit]]''' - An [[orbit]] that appears to a ground observer to be orbiting a certain  [[planet]] but is actually in [[Co-orbital satellite|co-orbit]] with the [[planet]]. See asteroids [[3753 Cruithne|3753]] (Cruithne) and [[2002 AA29|2002 AA<sub>29</sub>]].
:'''[[Exo-orbit]]''' - A maneuver where a [[spacecraft]] approaches the height of [[orbit]] but lacks the [[velocity]] to sustain it. 
::'''[[Orbital spaceflight|Orbital Spaceflight]]''' - A [[synonym]] for [[Exo-orbit]].
:'''[[Lunar transfer orbit]] (LTO)''' -
:'''[[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.  Almost no 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]].
<!--
'''[[Decaying orbit]]''' - See [[orbital decay]].
-->
Satellites can also orbit [[Lagrangian Point]]s.
==Launch capable countries==
{{main|Timeline of first orbital launches by nationality}}
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 &mdash; which relatively speaking, does not require much economic, scientific and industrial capacity &mdash; 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.  Does not include consortium satellites or multi-national satellites.
<center>
Full '''Space powers''' - owning by the independently developed  launch vehicles:
{| class="wikitable"
|+ '''First launch by country'''
|- bgcolor=#efefef
! Country || Year of first launch || First satellite || Launches to orbit in 2006[http://www.celestrak.com/satcat/boxscore.asp]
|-
|align="left"| {{flagcountry|Soviet Union}}<br>(followed now by Russia and Ukraine) || 1957 || ''[[Sputnik 1]]'' || 1390
|-
|align="left"| {{flagcountry|United States}} || 1958 || ''[[Explorer 1]]'' || 999
|-
|align="left"| {{flagcountry|France}} || 1965 || ''[[Astérix (satellite)|Astérix]]'' || ?
|-
|align="left"| {{flagcountry|Japan}} || 1970 || ''[[Osumi (Satellite)|Osumi]]'' || ?
|-
|align="left"| {{flagcountry|China}} || 1970 || ''[[Dong Fang Hong I]]'' || 53
|-
|align="left"| {{flagcountry|United Kingdom}} || 1971 || ''[[Prospero X-3]]'' || ?
|-
|align="left"| {{flagcountry|India}} || 1981 || ''[[Rohini space satellite|Rohini]]'' || ?
|-
|align="left"| {{flagcountry|Israel}} || 1988 ||''[[Ofeq|Ofeq 1]]'' || 6
|-
<!--Please do not add Italy and Kazakhstan, see below, and on talk page for details-->
|}
</center>
Both [[North Korea]] ([[1998]]) and [[Iraq]] ([[1989]]) have claimed orbital launches but these are unconfirmed. 
In any time earlier some other countries such as [[South Africa]], [[Spain]], [[Italy]], [[West Germany]], [[Canada]], [[Australia]], [[Argentina]], [[Egypt]], etc and private companies such as [[OTRAG]], etc fulfilled the development of own launchers, but not realized ones.
[[As of 2007]], only 7 countries from list above (six 'major' - [[Russia]] and [[Ukraine]] instead of [[USSR]], also [[USA]], [[Japan]], [[China]], [[India]], and 1 'minor' - [[Israel]]) and one regional organisation ([[European Union]] presented by [[European Space Agency|European Space Agency (ESA)]]) have independently launched satellites on their own indigenously developed launch vehicles. (The launch capabilities of the [[United Kingdom]] and [[France]] now fall under the [[ESA]].)
Also one international private company ([[Sea Launch]]) has the launch capability by their purchasing of Ukrainian-Russian launchers.
Several other countries such as [[Brazil]], [[Iran]], [[South Korea]], [[Malaysia]], [[Pakistan]], [[Turkey]], etc are in the closest or early stages of developing their own small-scale launcher capabilities, and seek the membership in the club of space powers - others may have the scientific and industrial capability, but not the economic or political will.
<center>
'''Space powers''' extently - owning by the independently developed satellites:
{| class="wikitable"
|+ '''First launch by country including help of another parties'''
|- bgcolor=#efefef
! Country || Year of first launch || First satellite || Payloads in orbit in 2006[http://www.celestrak.com/satcat/boxscore.asp]
|-
|align="left"| {{flagcountry|Soviet Union}}<br>(followed now by Russia and Ukraine) || 1957 || ''[[Sputnik 1]]'' || 1390
|-
|align="left"| {{flagcountry|United States}} || 1958 || ''[[Explorer 1]]'' || 999
|-
|align="left"| {{flagcountry|Canada}} || 1962 || ''[[Alouette 1]]'' || 33
|-
|align="left"| {{flagcountry|France}} || 1965 || ''[[Astérix (satellite)|Astérix]]'' || 43
|-
|align="left"| {{flagcountry|Italy}} || 1967 || ''[[San Marco 2]]'' ||
|-
|align="left"| {{flagcountry|Australia}} || 1967 || ''[[WRESAT]]'' ||
|-
|align="left"| {{flagcountry|Japan}} || 1970 || ''[[Osumi (Satellite)|Osumi]]'' || 102
|-
|align="left"| {{flagcountry|China}} || 1970 || ''[[Dong Fang Hong I]]'' || 53
|-
|align="left"| {{flagcountry|United Kingdom}} || 1971 || ''[[Prospero X-3]]'' || 23
|-
|align="left"| {{flagcountry|India}} || 1981 || ''[[Rohini space satellite|Rohini]]'' || 31
|-
|align="left"| {{flagcountry|Israel}} || 1988 ||''[[Ofeq|Ofeq 1]]'' || 6
|-
|align="left"| {{flagcountry|Egypt}} || 1998||''[[NileSat 101]]'' || 3
|-
|align="left"| {{flagcountry|Kazakhstan}} || 2006 || ''[[KazSat|KazSat 1]]'' || 1
|}
</center>
While [[Canada]] was the third country to build a satellite which was launched into Space, it was launched aboard a U.S. rocket from a U.S. spaceport.  The same goes for [[Australia]], who launched on-board a donated Redstone rocket. The first Italian-launched was [[San Marco 2]], launched on [[26 April]], [[1967]] on a U.S. [[Scout rocket]] with U.S. support.[http://nssdc.gsfc.nasa.gov/database/MasterCatalog?sc=1967-038A] [[Australia]]'s launch project, in November 1967, involved a donated U.S. missile and U. S. support staff as well as a joint launch facility with the [[United Kingdom]].[http://homepage.powerup.com.au/~woomera/wresat.htm]
[[Kazakhstan]] claimed that did launch their satellite independently, but satellite was built by the Russian help.
==Heraldry==
The (artificial, though this is not stated in the blazon) satellite appears as a [[charge (heraldry)|charge]] in the arms of [[Arthur Maxwell House]].<ref>http://heraldry.ca/arms/h/house.htm</ref> This is in addition to numerous appearances of the natural satellite the [[moon]], and the moons of the [[planet]]s [[Jupiter (planet)|Jupiter]] and [[Saturn (planet)|Saturn]] (with those planets) in the arms of [[Pierre Laplace|Pierre-Simon LaPlace]].
==See also==
[[Image:Satellite.JPG|thumbnail|right|A model satellite in a museum]]
* [[Communications satellite]]
* [[Timeline of artificial satellites and space probes]]
* [[List of Earth observation satellites]]
* [[International Designator]]
* [[Satellite Catalog Number]]
* [[Miniaturized satellite]]
* Satellites (sorted by launch date):
** [[Syncom]] 1 ([[1963]]), 2 (1963) and 3 (1964)
** [[Anik 1]] (1972)
** [[EgyptSat 1]] (2007) (Egypt, launched by Ukraine)
** Egypt to launch its first scientific satellite http://www.scidev.net/gateways/index.cfm?fuseaction=readitem&rgwid=2&item=News&itemid=1284&language=1
** [[Aryabhata (satellite)|Aryabhata]] (1975) (India, launched by USSR)
** [[Hermes Communications Technology Satellite]] (1976)
** [[Experimental geodetic payload]] (1986)
** [[Munin (satellite)|Munin]] (2000) (Sweden, launched by U.S.)
** [[KEO]] satellite - a space [[time capsule]] (2006)
* Satellite Services:
** [[Satellite phone]]
** [[Satellite Internet]]
** [[Satellite television]]
** [[Satellite radio]]
* [[Anti-satellite weapon]]
* [[GoldenEye (fictional satellite weapon)|GoldenEye]] (fictional satellite weapon)
* [[Tether satellite]]
{{Met_inst}}
==References==
<references />
==External links==
* [http://en.satellite.tracks.free.fr Satellite Ground Tracks] Real time satellite's tracks (Full catalog of satellite orbit). {{en}} (deutsch) {{es}} {{fr}} {{it}} (portugues) {{zh}}
* [http://www.vega.org.uk/video/programme/12 'Eyes in the Sky' Free video by the Vega Science Trust and the BBC/OU]Satellites and their implications over the last 50 years.
* [http://science.howstuffworks.com/satellite.htm How Stuff Works.com]  How satellites work
*[http://www.ucsusa.org/global_security/space_weapons/satellite_database.html UCS Satellite Database] Lists operational satellites currently in orbit around the Earth. Updated quarterly.
* [http://www.edusat.info Edusat project]
* [http://www.lsi.usp.br/~rbianchi/clarke/ACC.ETRelaysFull.html Facsimile of Arthur C. Clarke's 1945 paper on communication satellites]
* [http://www.oosa.unvienna.org UN Office for Outer Space Affairs] ensures all countries benefit from satellites
* [http://archives.cbc.ca/IDD-1-75-92/science_technology/satellites/ CBC Digital Archives - Launching the Digital Age: Canadian Satellites]
* [http://informationvision.net/default.aspx 'Student Satellite Project'] Student Satellite Project for Pakistani and International Students. This site contains information and documents about satellite projects.
*[http://www.orbitaldebris.jsc.nasa.gov/ NASA Orbital Debris Program Office]
*[http://www.soundboard.com/sb/Space_Satellite_Sound.aspx Sounds from the first Satellites at Soundboard.com]- with audio clips of First Satellites
'''
[[Category:Satellites| ]]
[[Category:Unmanned vehicles]]
[[af:Satelliet]]
[[ar:قمر اصطناعي]]
[[bs:Sateliti]]
[[bg:Изкуствен спътник]]
[[ca:Satèl·lit artificial]]
[[cs:Umělá družice]]
[[cy:Lloeren]]
[[da:Satellit]]
[[de:Satellit (Raumfahrt)]]
[[et:Tehiskaaslane]]
[[el:Τεχνητός δορυφόρος]]
[[es:Satélite artificial]]
[[eo:Artefarita satelito]]
[[eu:Satelite artifizial]]
[[fa:ماهواره]]
[[fr:Satellite artificiel]]
[[gl:Satélite artificial]]
[[ko:인공위성]]
[[hr:Satelit]]
[[id:Satelit]]
[[ia:Satellite]]
[[it:Satellite artificiale]]
[[he:לוויין]]
[[ka:ხელოვნური თანამგზავრი]]
[[lv:Pavadonis]]
[[lb:Satellit (Raumfaart)]]
[[lt:Dirbtinis palydovas]]
[[hu:Műhold]]
[[nl:Kunstmaan]]
[[ja:人工衛星]]
[[no:Kunstig satellitt]]
[[pl:Sztuczny satelita]]
[[pt:Satélite artificial]]
[[ru:Искусственный спутник Земли]]
[[simple:Satellite]]
[[sk:Umelá družica]]
[[sl:Satelit]]
[[sr:Сателит]]
[[fi:Satelliitti]]
[[sv:Satellit]]
[[th:ดาวเทียม]]
[[vi:Vệ tinh]]
[[yi:סאטעליט]]
[[zh:人造衛星]]

Revision as of 10:56, 9 July 2007

In the context of spaceflight, satellites are objects which have been placed into orbit by human endeavor. They are sometimes called artificial satellites to distinguish them from natural satellites such as the Moon.

History

The first artificial satellite was Sputnik 1, launched by the Soviet Union on 4 October 1957. This triggered the Space Race between the Soviet Union and the United States.