Clairaut Alexis-Claude

1713-1758

The son of a mathematician, Clairaut showed very early gifts in mathematics, so that he was elected in 1731 to the Academy of Sciences without having reached the legal age. In 1736, he participated in the expedition to Lapland intended to determine the shape of the Earth. On his return, he published his Theory of the Figure of the Earth where he showed the relationship between the rotation and the flattening of an inhomogeneous deformable body. An early proponent in France of Newton’s theory of universal gravitation, he produced in 1752 on this basis a theory of the Moon, which represented a very significant advance in celestial mechanics. In 1759, assisted by Nicole-Reine Lepaute and the young Lalande, he addressed the problem of the perturbation of the motion of comets by the planets and successfully predicted a significant delay in the return of Halley’s comet. This work ensured the final success of Newton’s theories in France. His fairly dissolute life caused, according to his contemporaries, his untimely death.