Artificial satellites orbiting in space have various functions, such as emitting telecommunication signals, collecting information for strategic purposes or predicting the behavior of the weather. In any case, the satellites collect images that allow us to analyze all kinds of realities.
When talking about images, do not be confused what is a satellite image of a photograph. The image is any graphic representation that identifies and records electromagnetic energy and photography is dependent on light. Therefore, a photograph is a specific type of image.
As we know them today, satellite images began to be used in the late 1950s, when satellite platforms replaced electronic sensors on aircraft. In this sense, there was a real revolution in meteorology, in the telecommunications sector and in military strategy.
Technical aspects of satellite images
Image pixels are fixed in size and correspond to a specific area of terrain.
Satellite imagery sensors detect diverse information within different wavelength ranges. Typically, different digital bands are used to display an image with the three primary colors, red, green, and blue.
The advantages of satellite images
First of all, these are images that can be obtained very quickly and immediately. In fact, it can now be done instantly over the internet.
They allow to know areas of great extension and at a low cost.
It is possible to access very remote places, since borders disappear from space and this allows it to be possible to capture any place on the planet no matter how remote it may be.
The information from the images can be combined with other information systems, such as GIS or Geographic Information Systems.
From the point of view of human curiosity, these images allow us to move virtually as if we were really in a real place.
Despite the advantages of this type of image, it must be taken into account that the image obtained presents a series of interferences that disturb the information.
Photos: Fotolia - Jim - Riko Best
