Giovanni Cassini - AbsoluteAstronomy.com

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Giovanni Cassini

Giovanni Cassini (1625-1712) was a French-Italian astronomer whose observational work in astronomy led a several notable discoveries of objects in the solar system.

Cassini is best know for his discovery of four of Saturn's moons: Iapetus, Rhea, Tethys, and Dione. He is also credited with discovering the Great Red Spot on Jupiter. In 1665, Cassini observed gaps in the rings of Saturn. These gaps would later come to be known as the Cassini Division.

He is also known for measuring the rotational periods of Mars and Jupiter.

Fact Sheet

Born		June 8, 1625 in Perinaldo, Italy
Died		September 12, 1712 in Paris, France
Nationality		French-Italian
Religion		Roman Catholic
Fields		Astronomy, Astrology
Achievements		First to observe differential rotation within Jupiter's atmosphere. First to make accurate measurements of longitude in mapmaking.
Discoveries		- The Great Red Spot on Jupiter (1665). - Saturn moons Iapetus, Rhea, Tethys, and Dione - Discovered that Saturn's Rings are separated into gaps, now called Cassini Division. - Discovered the light-time effect