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What role did John Couch Adams play in the discovery of Neptune?

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Clouds in Neptune's atmosphere — Neptune A photograph of clouds in Neptune's atmosphere, taken by Voyager 2 in August 1989. The view is from below the planet's equator, and north is up. The Great Dark Spot (center left) is 13,000 km (8,100 miles)—about the diameter of Earth—in its longer dimension. Accompanying it are bright, wispy clouds thought to comprise methane ice crystals. At higher southern latitudes lies a smaller, eye-shaped dark spot with a light core (bottom left). Just above that spot is a bright cloud dubbed Scooter. Each of these cloud features was seen to travel eastward but at a different rate, the Great Dark Spot moving the slowest.

John Couch Adams was a British mathematician and astronomer who independently predicted the existence and location of Neptune by analyzing irregularities in the orbit of Uranus.21

Beginning his study in 1843, Adams sought to determine if the gravitational influence of an undiscovered planet was causing the observed deviations in Uranus's path. By September 1845, he had provided accurate calculations of the planet's predicted position to James Challis, the director of the Cambridge Observatory. However, the search at Cambridge was delayed and ultimately unsuccessful in identifying the planet before its discovery elsewhere.123

While the French astronomer Urbain-Jean-Joseph Le Verrier performed similar calculations independently, the actual visual identification of Neptune occurred on September 23, 1846, at the Berlin Observatory by Johann Gottfried Galle and Heinrich Louis d’Arrest. Although historical consensus eventually credited both Adams and Le Verrier with the discovery, modern analysis suggests Adams's contribution may have been less substantial than previously believed.14