Urbain Le Verrier

Le Verrier used mathematical analysis of irregularities in the orbit of Uranus to predict the position of an unseen planet beyond it in 1846. He sent his calculations to the Berlin Observatory, where Johann Gottfried Galle discovered Neptune within approximately one degree of Le Verrier's predicted location. The discovery was made on the night of September 23, 1846.

Yes, the English astronomer John Couch Adams had performed similar calculations independently before Le Verrier, but his work did not lead directly to the observational discovery. Le Verrier's predictions were the ones that prompted Galle's successful telescope search in Berlin. The question of scientific priority between Adams and Le Verrier sparked a famous dispute between British and French astronomers.

Le Verrier also studied the anomalous precession of Mercury's perihelion and attributed the discrepancy to an undiscovered planet between Mercury and the Sun, which he named Vulcan. No such planet was ever found despite numerous claimed sightings. The Mercury anomaly was later explained by Einstein's general theory of relativity in 1915.

Le Verrier spent much of his career at the Paris Observatory, serving as its director. He was educated at the École Polytechnique in Paris and was born in Saint-Lô, Normandy, in 1811. He held positions in celestial mechanics and was elected to the French Academy of Sciences.