Satellite

:''For other uses, please see Satellite (disambiguation)'' A satellite is an object that orbits another object (known as its ''primary''). The term is often used to describe an artificial satellite (as opposed to natural satellite, or moons). Because all objects exert gravity, the motion of the primary object is also affected by the satellite. (This observation allows for the discovery of extrasolar planets.) If two objects are sufficiently similar in mass, they are generally referred to as a binary system (astronomy) rather than a primary object and satellite. The general criterion for an object to be a satellite is that the center of mass of the two objects is inside the other object. All masses that are part of the solar system, including the Earth, are satellites of the Sun, or satellites of those objects, such as the Moon. [[Image:Venera-7_diagram.jpg|thumb|The Russian Venera 7 satellite]] ==Artificial satellites== ===History of artificial satellites=== In May, 1946, the Preliminary Design of an Experimental World-Circling Spaceship stated, "A satellite vehicle with appropriate instrumentation can be expected to be one of the most potent science tools of the 1900s. The achievement of a satellite craft would produce repercussions comparable to the explosion of the atomic bomb..." (see: Project RAND) The space age began in 1946^{The Radiation Belt and Magnetosphere}, as scientists began using captured Germany V-2 rockets to make measurements in the upper atmosphere. Before this period, scientists could use balloons up to kilometer and radio waves to study the ionosphere; rockets changed that. From 1946 to 1952, upper-atmosphere research was conducted using V-2s and Aerobee rockets. This allowed measurements of Earth's atmosphere pressure, density, and temperature up to 200 kilometre. (see also: magnetosphere, Van Allen radiation belt) The United States had been considering launching orbital satellites since 1945 under the Bureau of Aeronautics of the United States Navy of the United States Navy. The United States Air Force 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 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) 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 and on October 4, 1957 Sputnik I was launched into orbit, which triggered the Space Race between the two nations. The largest artificial satellite currently orbiting the earth is the International Space Station, which can sometimes be seen with the human eye. ===Types of satellites=== Astronomical satellites are satellites used for observation of distant planets, galaxies, and other outer space objects. Communications satellites are artificial satellites stationed in space for the purposes of telecommunications using radio at microwave frequencies. Most communications satellites use geosynchronous orbits or near-geostationary orbits, although some recent systems use low Earth orbiting satellites. Earth observation satellites are satellites specifically designed to observe Earth from orbit, similar to reconnaissance satellites but intended for non-military uses such as environmental monitoring, meteorology, map making etc. Navigation 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 satellites are Earth observation satellite or communications satellite deployed for military or espionage applications. Solar power satellites are proposed satellites built in high Earth orbit that use microwave power transmission to beam solar power to very large Antenna (electronics) on Earth where it can be used in place of conventional power sources. Space stations are man-made structures that are designed for human to live on in outer space. A space station is distinguished from other manned spacecraft by its lack of major Spacecraft propulsion or landing facilities — 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 weeks, months, or even years. Weather satellites are satellites that primarily are used to monitor the weather and/or climate of the Earth. Miniaturized satellites are satellites of unusually low weights and small sizes. New classifications are used to categorize these satellites: minisatellite (500–200 kg), microsatellite (below 200 kg), nanosatellite (below 10 kg). ==See also== * Timeline of artificial satellites and space probes * Satellites (by Launch Date) ** Syncom 1 (1963 ), 2 (1963) and 3 (1964) ** Anik 1 (1972) ** Hermes Communications Technology Satellite (1976) ** KEO satellite - a space time capsule (2006) * Satellite Services ** Satellite phone ** Satellite Internet ** Satellite television ==Reference== *1 -- The Radiation Belt and Magnetosphere ==External links== * [http://space.skyrocket.de Gunter's Space Page - Lists of nearly all satellites] * [http://www.ee.surrey.ac.uk/Personal/L.Wood/constellations/ Lloyd's satellite constellations] * [http://www.heavens-above.com/ Welcome to Heavens-Above!]has everything, customized searchable catalogue * [http://science.nasa.gov/Realtime/JPass/20/ J-Pass] NASA site for satellite-watching * [http://science.nasa.gov/RealTime/JTrack/3D/JTrack3D.html J-Track 3D] NASA site displaying a globe with orbiting satellites. * [http://ilectric.com/glance/Recreation/Radio/Amateur/Satellite_Tracking/ Satellite Tracking in Recreation Radio Amateur] an excellent link to many links * [http://www.oosa.unvienna.org UN Office for Outer Space Affairs] ensures all countries benefit from satellites * [http://www.satelliteradioreview.com Satellite Radio] * [http://www.lamit.ro Satellite Internet] * [http://satobs.org/ Visual Satellite Observer's Home Page] * [http://www.space-track.org/perl/login.pl Space-Track] The U.S. Department of Defense (DoD)'s Space-Track.org website. Provides a 60 Day Decay Prediction of expected re-entries of objects in unclassified orbits. For objects near decay, the site provides Trajectory Impact Prediction (TIP) messages, which estimate the time and location of decay. * [http://celestrak.com/NORAD/elements/ Norad TLE] Obtain TLE for various satellites tracked by NORAD. * [http://www3.telus.net/public/boucherd/main.htm Earth Orbit Objects] Free Satellite Tracking and Pass Prediction Program. Download TLE sets directly from Space-Track.org. * [http://www.terrasat.microsoft.com Terra Link] Satellites

Satellite

#REDIRECT Talk:Artificial satellite

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Words begining with Satellite:

Satellite
Satellite
Satellites
Satellites
Satellites_of_Jupiter
Satellite_(album)
Satellite_(album)
Satellite_(biology)
Satellite_(disambiguation)
Satellite_(disambiguation)
Satellite_(Nintendo)
Satellite_1958_Alpha
Satellite_antenna
Satellite_Beach
Satellite_Beach,_FL
Satellite_Beach,_Florida
Satellite_cells
Satellite_cities
Satellite_city
Satellite_communication
Satellite_communications
Satellite_cone
Satellite_constellation
Satellite_country
Satellite_country
Satellite_Data_System
Satellite_dish
Satellite_dishes
Satellite_dish_installation
Satellite_dish_installation
Satellite_DNA
Satellite_earth_station
Satellite_flare
Satellite_geodesy
Satellite_image
Satellite_imagery
Satellite_images
Satellite_images
Satellite_Images_of_Continents
Satellite_Images_of_Continents
Satellite_images_of_continents
Satellite_images_of_continents
Satellite_images_of_the_continents
Satellite_Image_Comparison
Satellite_imaging
Satellite_imaging
Satellite_Internet
Satellite_internet
Satellite_laser_ranging
Satellite_laser_ranging
Satellite_link
Satellite_Master_Antenna_Television
Satellite_media_tour
Satellite_modem
Satellite_Music_Network
Satellite_nation
Satellite_navigation
Satellite_navigation_system
Satellite_navigation_system
Satellite_navigation_systems
Satellite_navigation_systems
Satellite_news_gathering
Satellite_nucleic_acid
Satellite_Observatory
Satellite_Of_Love
Satellite_of_Love
Satellite_of_Love_(MST3K)
Satellite_phone
Satellite_phone
Satellite_Phones
Satellite_Phones
Satellite_photo
Satellite_photography
Satellite_poker_tournament
Satellite_positioning_system
Satellite_Radio
Satellite_radio
Satellite_radio
Satellite_Records
Satellite_state
Satellite_state
Satellite_states
Satellite_states
Satellite_telephone
Satellite_television
Satellite_television
Satellite_television
Satellite_Television_Limited
Satellite_temperature_measurements
Satellite_temperature_measurements
Satellite_temperature_record
Satellite_tournaments
Satellite_town
Satellite_town
Satellite_TV
Satellite_tv
Satellite_virus