Related topics: nasa

Image: Mato Grosso, Brazil

The Copernicus Sentinel-1 mission takes us over part of the Brazilian state of Mato Grosso deep in the Amazon interior.

French earthquake fault mapped

This week, southeast France was hit by a magnitude 5 earthquake with tremors felt between Lyon and Montélimar. The Copernicus Sentinel-1 radar mission has been used to map the way the ground shifted as a result of the quake.

Combining satellites, radar provides path for better forecasts

Every minute counts when it comes to predicting severe weather. Combing data from cutting-edge geostationary satellites and traditional weather radar created a path toward earlier, more accurate warnings, according to Penn ...

World's first production of aluminum scandium nitride via MOCVD

Scientists at the Fraunhofer Institute for Applied Solid State Physics IAF have achieved what was previously considered impossible: They are the first in the world who have managed to manufacture aluminum scandium nitride ...

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Radar is an object detection system that uses electromagnetic waves to identify the range, altitude, direction, or speed of both moving and fixed objects such as aircraft, ships, motor vehicles, weather formations, and terrain. The term RADAR was coined in 1941 as an acronym for radio detection and ranging. The term has since entered the English language as a standard word, radar, losing the capitalization. Radar was originally called RDF (Radio Direction Finder, now used as a totally different device) in the United Kingdom.

A radar system has a transmitter that emits microwaves or radio waves. These waves are in phase when emitted, and when they come into contact with an object are scattered in all directions. The signal is thus partly reflected back and it has a slight change of wavelength (and thus frequency) if the target is moving. The receiver is usually, but not always, in the same location as the transmitter. Although the signal returned is usually very weak, the signal can be amplified through use of electronic techniques in the receiver and in the antenna configuration. This enables radar to detect objects at ranges where other emissions, such as sound or visible light, would be too weak to detect. Radar is used in meteorological detection of precipitation, measuring ocean surface waves, air traffic control, police detection of speeding traffic, and by the military.

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