Christiaan Huygens

Born in 1629 to a prominent Dutch family, Huygens moved through mathematics, mechanics, and astronomy with a precision that turned guesswork into geometry. In 1655 he and his brother ground lenses and built telescopes; with one he spotted Titan and solved Saturn's appearance as a flat ring tilted around the planet. He patented the pendulum clock in 1657, then spent the next decade analyzing its motion in Horologium Oscillatorium (1673), a text on curves and mechanics that stood among the century's peaks. He derived the formula for centrifugal force in 1659, a decade before Newton, and in 1656 worked out the laws of elastic collision - published only after his death in 1703. His wave theory of light, described in Traité de la Lumière (1690), was shelved for Newton's particles until Fresnel revived it in 1821. He died in 1695, having written the first treatise to idealize a physical problem in pure mathematical terms.