Picture of Giovanni Cassini
Corbis-Bettmann

Giovanni Cassini

Giovanni Cassini was Italian-French astronomer who lived between 1625-1712. He discovered that Saturn's Rings are split into two parts, and today the gap between them is called the "Cassini Division". He also discovered four of Saturn's moons, in addition to those found by Huygens twenty years earlier.

Cassini studied hydrology and how to avoid the damaging floods that plagued Europe. His greatest mistakes were rejecting the Copernican model of the solar system and Newton's theory of universal gravitation.

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