Semiconductors

Broadcom announces development of more precise GPS chip

(Tech Xplore)—Broadcom Limited, a wholly owned subsidiary of Avago Technologies, has announced the development of a new GPS chip, the BCM47755, which the company claims is far more accurate than the conventional chips now ...

Computer Sciences

Computer approaches human skill for first time in mapping brain

A WSU research team for the first time has developed a computer algorithm that is nearly as accurate as people are at mapping brain neural networks—a breakthrough that could speed up the image analysis that researchers ...

Engineering

Satellite radar system used to help preserve Angkor Wat temple

(Tech Xplore)—A team of researchers from several institutions in China and one in Cambodia has used a new type of satellite radar system to assess the likelihood of damage to the iconic Angkor Wat temple from higher amounts ...

Engineering

A high-speed motor for satellites

A dizzying 150,000 revolutions per minute: researchers from ETH Zurich (Department of Information Technology and Electrical Engineering) and the ETH spin-off Celeroton have developed an ultra-fast magnetically levitated electric ...

Engineering

Russian team attempts crowdfunding for space junk solution

Space junk is as bothersome as it sounds. "Space exploration hasn't been on for long, but humanity has already managed to turn near-Earth space into a miniature junk yard for satellites," said a Russian team. These days, ...

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Satellite

In the context of spaceflight, a satellite is an object which has been placed into orbit by human endeavor. Such objects are sometimes called artificial satellites to distinguish them from natural satellites such as the Moon.

The first artificial satellite, Sputnik 1, was launched by the Soviet Union in 1957. By 2009 thousands of satellites have been launched into orbit around the Earth. These originate from more than 50 countries and have used the satellite launching capabilities of ten nations. A few hundred satellites are currently operational, whereas thousands of unused satellites and satellite fragments orbit the Earth as space debris. A few space probes have been placed into orbit around other bodies and become artificial satellites to the Moon, Venus, Mars, Jupiter and Saturn.

Satellites are used for a large number of purposes. Common types include military (spy) and civilian Earth observation satellites, communication satellites, navigation satellites, weather satellites, and research satellites. Space stations and human spacecraft in orbit are also satellites. Satellite orbits vary greatly, depending on the purpose of the satellite, and are classified in a number of ways. Well-known (overlapping) classes include low Earth orbit, polar orbit, and geostationary orbit.

Satellites are usually semi-independent computer controlled systems. Satellite subsystems attend many tasks, such as power generation, thermal control, telemetry, attitude control and orbit control.

This text uses material from Wikipedia, licensed under CC BY-SA