John Couch Adams (astronomer) (1819-1892), English astronomer and mathematician, who predicted the existence of the planet Neptune. He was born in Laneast, Cornwall, England, and attended Saint Johns College at the University of Cambridge. Based on unexplained irregularities in the motion of the planet Uranus, Adams suggested, in 1845, the existence of a more distant undiscovered planet. The same conclusion was reached by French astronomer Urbain Jean Joseph Leverrier about nine months later, and confirmed in 1846 by the discovery of Neptune near the position predicted by both scientists. Adams was appointed the Lowndean professor of astronomy and geometry at Cambridge in 1859 and director of the Cambridge Observatory in 1861. He later worked on the secular acceleration of the moon's mean motion and analyzed the perturbations of the Leonid meteors.