Exploratour - Evolution of the Solar System
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This picture shows the region of space where the Kuiper Belt is postulated to exist. In this picture, the observer is looking down on the solar system from above. The picture shows a region from the sun to 120 AU. The earth is so close to the center of the drawing that it does not show up.
The first object in the Kuiper Belt was discovered in 1992, proving that Gerard Kuiper's theory of 1951 was correct. Since then many objects have been discovered in this region, which is sometimes called "trans-Neptunian space" because even the planet Pluto could really be a Kuiper Belt object.
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