In 1821, Alexis Bouvard published the astronomical tables of the orbit of Uranus. Later observations showed that Uranus was moving in an irregular way in its orbit. Therefore some astronomers thought of another large body. In 1843, John Couch Adams calculated the orbit of an eighth planet that would possibly be influencing the orbit of Uranus. He sent his calculations to Sir George Airy, the Astronomer Royal, who asked Adams for an explanation. In 1846, Urbain Le Verrier, who was not working with Adams, made his own calculations but also failed to get much attention from French astronomers. However, in the same year, John Herschel began to support the mathematical method and encouraged James Challis to search for the planet. After much delay, Challis began his unwilling search in July 1846. Meanwhile, Le Verrier had convinced Johann Gottfried Galle to search for the planet.