for scene 4 of the video " Kepler Today - Part 1 - The Science Revolution" by Rolf Witzsche - Ice Age Ahead not Global
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Kepler discovered the laws
Kepler discovered the laws by which a gravity-bound system of orbiting planets must necessarily operate in order to exist.
In an orbital system the force of the central gravity (the Sun) must be balanced by the centrifugal force of the orbiting planet. This requirement demands a unique pattern of velocity to distance relationships, which is common for all orbital system by the requirement of the principle involved. Kepler discovered this principle.
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