"Alexis Claude de Clairault (or Clairaut) (born May 7 or May 13, 1713, died May 17, 1765) - French mathematician.
At the age of 12 in 1725, he presented his first scientific treatise on curved lines before members of the Royal Academy of Sciences. In 1731 he became a member of this Academy. In April 1736 he embarked on a scientific expedition to Lapland to study the flattening of the globe (concluded 1737 by demonstrating the correctness of Newton's thesis). Clairaut then compiled a work on the shape of the Earth and the planets. Together with Joseph-Jérôme Lalande and Nicole-Reine Étable de la Brière-Lepaute, he showed that the comet appearances of 1531, 1607 and 1682 were actually of a single celestial body. He calculated the date of the next appearance with an accuracy of 33 days."
