1677-1756

Italian astronomer who fervently supported René Descartes' prediction that Earth is a prolate spheroid—elongated polar axis—against Isaac Newton's prediction that it is an oblate spheroid—bulging equator and flattened poles. Cassini adopted the Cartesian view after participating in his father's extension of the Paris meridian (1700-01). Results from this and other geodesic work seemed to support Descartes' hypothesis. Expeditions to Peru (1734-44) and Lapland (1736) later settled the debate decisively in favor of Newton.