Читать книгу Geography For Dummies - Jerry T. Mitchell - Страница 116

Getting information remotely is the game, here. In other words, someone — or rather, something — is doing the work for you. In remote sensing we are talking about gathering information at a distance, and mainly about Earth from above. This might be aerial photography from a balloon all the way to infrared imagery from a satellite hundreds of miles above you, and much of this information now makes up the base maps used in a GIS.

Numerous satellites monitor and provide map-ready information about Earth’s surface and atmosphere. Virtually all of them utilize non-photographic scanners that produce thermal, infrared, or radar imagery. This information is processed and assembled into photo-like images. But we also use digital photography taken by aircraft or drone, and each type of sensor has special advantages.