Remote sensing is the collection of information about objects or processes without direct contact. It is used in various fields, including satellite mapping, weather monitoring, and topographic mapping. Remote sensing can be passive or active, and data is often analyzed by computers for efficiency and accuracy.
Remote sensing is the science of obtaining information about something such as an object or a process without direct physical contact, usually because such contact is impossible or very expensive to obtain. Information obtained via remote sensory techniques may simply involve observation, such as an image taken by an aerial camera, or it may involve more nuanced measurements, such as sonar, which is used to gather data for both distance and size measurements. Remote sensory techniques are used in many different fields, including biology, chemistry and physics. In most cases, however, “remote sensing” refers to techniques used to collect images and data about objects on Earth from a distance; satellite mapping of the Earth is one example.
Some forms of remote sensing, such as photography, are passive, simply gathering information that is already there. A camera, for example, emits nothing; instead it produces images based on the reflected light already present in the environment. Other forms of remote sensing, however, use active techniques to gather information. Active sonar systems, for example, work by emitting bursts of sound and using the echoes to gather information about distant objects from a distance. It is an active method because sound pulses must be emitted before information of any form can be gathered.
The applications of remote sensing are numerous, as there are many objects and phenomena about which it is difficult to obtain information directly. Radar, for example, is used to monitor weather conditions remotely; measure the speed of drivers; and supervising air traffic, particularly around airports. Also, aerial photography methods are used to develop aerial maps. Some aerial photography techniques can also be used to create topographic maps, which provide detailed terrain and elevation information. Still other forms of remote sensing are used to measure earthquakes, remote weapons, measure atmospheric chemical concentrations, and measure the radiation emitted.
Much of the data obtained through remote sensing methods is analyzed by computers because computers can analyze information much more efficiently and accurately than humans can. Computer algorithms, for example, are often used to distinguish valuable data from instrumentation noise. Computers can be used to clean up the images and to make quick calculations on the data obtained. Computer programs can also be used to accurately resize images. This is especially important when remote sensing methods are used to develop images of very large objects or areas, such as in aerial photography.
Protect your devices with Threat Protection by NordVPN
