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Launch-capable countries

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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. First launch by country Order Country Date of first launch Rocket Satellite(s) 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...
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Tracking

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Satellites can be tracked from Earth stations and also from other satellites. Space Surveillance Network edit The United States Space Surveillance Network (SSN), 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 (i.e. ~560 satellites), the rest are space debris. The United States Strategic Command is primarily interested in the active satellites, but also tracks space debris which ...
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Types

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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. (See especially Earth Observing 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 mete...
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