Alexis Bouvard


Alexis Bouvard was a French astronomer. He is particularly noted for his careful observations of the irregularities in the motion of Uranus and his hypothesis of the existence of an eighth planet in the solar system.

Life

Born in Contamines, Duchy of Savoy, Bouvard's achievements included the discovery of eight comets and the compilation of astronomical tables of Jupiter, Saturn and Uranus. While the former two tables were eminently successful, the latter showed substantial discrepancies with subsequent observations. This led Bouvard to hypothesise the existence of an eighth planet responsible for the irregularities in Uranus' orbit. The position of Neptune was subsequently calculated from Bouvard's observations by Urbain Le Verrier after his death.
Bouvard was eventually director of the Paris Observatory after starting there as a student astronomer in 1793 and working under Pierre-Simon Laplace. He died in Paris.

Honours