Alexis Clairaut

Alexis Claude Clairaut was a French mathematician, astronomer and physicist, born in 1713 and dying in 1765, and a prominent Newtonian whose work helped to establish the validity of the principles and results that Newton had outlined in the Principia of 1687. He was one of the key figures in the expedition to Lapland that helped to confirm Newton's deduction of the figure of the Earth, and from it he deduced what is now known as Clairaut's theorem. He also tackled the gravitational three-body problem, being the first to obtain a satisfactory result for the apsidal precession of the Moon's orbit. A treatise on tortuous curves, published in 1731 when he was below the legal age, brought him admission to the Royal Academy of Sciences, and he was elected a Fellow of the Royal Society of London in 1737.