Urbain Jean Joseph Le Verrier (French: [yʁbɛ̃ ʒɑ̃ ʒɔzɛf lə vɛʁje]; 11 March 1811 – 23 September 1877) was a French mathematician who specialized in celestial mechanics and is best known for predicting the existence and position of Neptune using only mathematics. The calculations were made to explain discrepancies with Uranus's orbit and the laws of Kepler and Newton. Le Verrier sent the coordinates to Johann Gottfried Galle in Berlin, asking him to verify.