Energy & Green Tech

Researchers create highest efficiency 1-sun solar cell

Researchers at the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) created a solar cell with a record 39.5% efficiency under 1-sun global illumination. This is the highest efficiency solar cell of ...

Automotive

How space is connecting cars

Today's connected cars are dynamic, updateable devices—and, because they can be updated, they are well equipped to become tomorrow's cars. ESA is working with European carmakers to ensure that connected vehicles harness ...

Computer Sciences

Neural network can read tree heights from satellite images

Using an artificial neural network, researchers at ETH Zurich have created the first high-resolution global vegetation height map for 2020 from satellite images. This map could provide key information for fighting climate ...

Telecom

The race to dominate satellite internet heats up

Though satellite internet has existed for years, the competition is about to rapidly intensify, with companies planning to launch thousands of their own systems into low Earth orbit.

Security

Satellite modems nexus of worst cyberattack of Ukraine war

A malicious software command that immediately crippled tens of thousands of modems across Europe anchored the cyberattack on a satellite network used by Ukraine's government and military just as Russia invaded, the satellite ...

Security

'Cyberattack' knocks thousands offline in Europe

Thousands of internet users across Europe have been thrown offline after what sources said Friday was a likely cyberattack at the beginning of Russia's offensive in Ukraine.

Telecom

Musk activates Starlink internet service in Ukraine

Elon Musk said Saturday his company SpaceX's Starlink satellite broadband service had been activated in Ukraine, after a Kyiv official urged the tech titan to provide his embattled country with stations.

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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