Eudoxus of Cnidus

Eudoxus of Cnidus was an ancient Greek mathematician and astronomer known for developing a sophisticated model to explain planetary movements. He proposed a system of concentric spheres—imagine layers of transparent, rotating shells—each carrying planets, to account for their complex paths in the sky. His approach helped early astronomers better predict planetary positions and influenced later models, including those of Aristotle and Ptolemy. Eudoxus's work was significant in advancing the understanding of celestial motions, laying groundwork for future astronomical theories.