Satellite

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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.

For more information about Satellite, read the full article at Wikipedia.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.

News tagged with satellite

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GOES-14 (O) moving into on-orbit storage around the Earth

Space & Earth / Space Exploration

3 hours ago | 5 / 5 (2) | 0

The Geostationary Operational Environmental Satellite named GOES-14, is being placed in on-orbit storage this month to await its call to duty.

Japan launches 5th spy satellite

Space & Earth / Space Exploration

Nov 28, 2009 | 3.5 / 5 (8) | 3

(AP) -- Japan launched its fifth spy satellite into orbit Saturday in a bid to boost its ability to independently gather intelligence, the government said.

China is set to launch its second moon orbiter next October, state media have reported

China to launch second lunar probe: state media

Space & Earth / Space Exploration

Nov 27, 2009 | 5 / 5 (6) | 0

China will launch its second moon orbiter next October, state media reported Friday, as it powers ahead with a space programme that has sparked concerns abroad.

NASA captures Typhoon Nida's clouds from 2 angles

Space & Earth / Earth Sciences

3 hours ago | not rated yet | 0

NASA satellites capture amazing views of tropical cyclones, and the Aqua and CloudSat satellites captured a top-down look at temperatures in Typhoon Nida's clouds, and an image of what they look like from ...

Aqua satellite sees Tropical Storm Bongani approaching Mozambique Channel

Space & Earth / Earth Sciences

Nov 25, 2009 | not rated yet | 0

NASA's Aqua satellite flew over Cyclone Bongani today and provided some important data that have helped forecasters figure out where the storm is headed, and helped them see that it has changed course.

NASA's Aqua satellite sees Nida explode into a category 5 Super typhoon

Space & Earth / Earth Sciences

Nov 25, 2009 | 4 / 5 (3) | 0

Typhoon Nida is in a favorable environment that has enabled it to intensify faster and stronger than previously forecast, and has now exploded into a Super typhoon. NASA's Aqua satellite passed over Nida and ...

Icebergs head from Antarctica for New Zealand

Space & Earth / Earth Sciences

Nov 24, 2009 | 3 / 5 (5) | 1

(AP) -- Ships in the south Pacific Ocean have been alerted that hundreds of icebergs believed to have split off Antarctic ice shelves are drifting north toward New Zealand, officials said Tuesday.

Ships warned about icebergs headed for New Zealand

Space & Earth / Earth Sciences

Nov 25, 2009 | not rated yet | 0

(AP) -- Ships are on alert and maritime authorities are monitoring the movements of hundreds of menacing icebergs drifting toward New Zealand in the southern Pacific Ocean, officials said.

NASA Assessing New Roles for Ailing QuikScat Satellite

Space & Earth / Space Exploration

Nov 24, 2009 | 4 / 5 (1) | 1

(PhysOrg.com) -- NASA mission managers are assessing options for future operations of the venerable QuikScat satellite following the age-related failure of a mechanism that spins the scatterometer antenna. ...