Recently I went to a boxing match in my home town to watch a couple of boxers "duke" it out. How did I find the section I was to sit in? The ticket had a series of numbers listing the section, row, and seat. Across the arena were fans sitting, in no particular organized manner, with different colored shirts. When viewed from a distance these groups of fans presented no particular image.

However, I have seen television football games where fans in the stadium seemed to present themselves as a picture, such as the mascot of one of the teams playing on the field. How did they do that? This activity will provide you with the understanding to develop the answer.

Looking at the image to the left you see a well organized picture of the southeastern United States. But looking at the image directly below it , you see no such organization, just the individual shades of gray.

To obtain an image like the first one, the computer must keep track of the row number, the seat number, and the shade of gray number. Without the tracking and placement in the correct order of the numbers, the image may well look like the second one. Obviously, the first image was produced by a satellite, but how did I obtain it, it certainly wasn't photographed and sent to earth in a parachute?

In reality, a satellite's imaging system, senses the reflected energy and assigns a "section, row, seat, and shade of gray color number" to the scene. Once complete, the satellite transmits the digital numbers via a radio signal and this signal is processed in the correct order to produce the image seen.

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