Machine learning & AI
For some of the poorest countries on Earth, the COVID-19 pandemic has posed a life-or-death quandary: If people continue to work, the virus might spread unchecked. But if they have to stay at home to limit the contagion, ...
Jun 3, 2020
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Electronics & Semiconductors
The 5G revolution has begun, and the first lines of phones that can access the next generation of wireless speeds have already hit the shelves. Researchers at The University of Texas at Austin and the University of Lille ...
May 26, 2020
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Computer Sciences
The ability to estimate the physical properties of objects is of key importance for robots, as it allows them to interact more effectively with their surrounding environment. In recent years, many robotics researchers have ...
Security
As European governments plan their phased recoveries from the lockdown states triggered by the COVID-19 pandemic, the positioning delivered through satellite navigation is becoming more important than ever before. Location ...
Apr 29, 2020
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Energy & Green Tech
NASA's long-term, global view of Earth from space includes data on sunlight, wind, temperature and precipitation, all key elements in understanding how our planet works. That same, information is also being put to very practical ...
Apr 21, 2020
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Software
A free app that helps people observe social distancing to slow the spread of coronavirus is about to launch.
Apr 20, 2020
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Engineering
Satellite imagery is a crucial aspect of modern life. For instance, crop growth and yield estimates are partially derived from satellite imagery; likewise, air quality, deforestation, and, of course, the weather. Satellite ...
Apr 20, 2020
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Energy & Green Tech
In 2019, the global population without access to electricity dipped below 1 billion for the first time. This progress has however been uneven, both across and within different regions. A new IIASA study shows that to ensure ...
Apr 17, 2020
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Internet
Academics from Heriot-Watt University have developed an antenna which, it is believed, will end the frustrations of billions of passengers each year who lose internet connectivity on journeys globally.
Feb 28, 2020
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Engineering
Many satellites are in space to take photos. But a vibrating satellite, like a camera in shaky hands, can't get a sharp image. Pointing it at a precise location to take a photo or perform another task, is another important ...
Feb 26, 2020
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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.
This text uses material from Wikipedia, licensed under CC BY-SA
