Observatiesatelliet, ERS 2
An observation satellite is a kind of artificial moon that is used to make maps, for example. They have powerful cameras on board who are able to observe everything on earth in detail. The cameras put patterns of light rays into radio signals and send them to ground stations on earth. There they are converted into photos, and check old maps for changes.
Landsat was the first observation satellite from the United States, launched in 1972.
SPOT is a European observation satellite, flying 830 kilometers high around the earth, laying a strip of 20 kilometers wide. SPOT is able to observe the entire planet in 26 days.
Other known observation satellites are: Externe link
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