Newton's idea of gravity

At the time of Isaac Newton, it was believed that the celestial bodies were moved by the so-called ether, a substance assumed to fill up all of space. But no one could prove the existence of this substance. Newton realized: rather than ether, there must be a universal action at a distance, originating from the celestial bodies themselves: the heavier a body is, the stronger its attraction. This is how the celestial bodies keep each other in their orbits. Author: ZDF/Terra X/ T. Schultes/ Aleks & Shantu Click here to see more videos:

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