AlegsaOnline.com Home Biographies Alexis Bouvard Alexis Bouvard Author: Leandro Alegsa Creation date: November 13, 2022 simple.wikipedia.org · Public domain Alexis Bouvard (June 27, 1767 – June 7, 1843) was a French astronomer. He is particularly noted for his careful observations of the irregulrities in the motion of Uranus and his hypothesis of the existence of an eighth planet in the solar system.