Leverrier, Urbain Jean Joseph definition of Leverrier, Urbain Jean Joseph in the Free Online Encyclopedia.

Leverrier, Urbain Jean Joseph (ürbăN` zhäN zhôzĕf` ləvĕryā`), 1811–77, French astronomer who made calculations that led to the discovery of the planet Neptune Neptune, in astronomy, 8th planet from the sun at a mean distance of about 2.8 billion mi (4.5 billion km) with an orbit lying between those of Uranus and the dwarf planet Pluto; its period of revolution is about 165 years.
..... Click the link for more information. . In considering the perturbations of Uranus Uranus (y

rā`nəs, y
..... Click the link for more information. , Leverrier made calculations indicating the presence of an unknown planet in an orbit outside that of Uranus. At the time, this was considered the crowning achievement of mathematical astronomy. The same conclusion had been reached by John Couch Adams Adams, John Couch, 1819–92, English astronomer, grad. St. John's College, Cambridge, 1843. By mathematical calculation based on irregularities in the motion of Uranus, he predicted the position of the then unknown planet Neptune.
..... Click the link for more information. a little earlier but had not been published, so Leverrier was initially given sole credit for the discovery of Neptune, which was actually first observed, as a result of Leverrier's instructions, by Johann Galle Galle, Johann Gottfried (yō`hän gôt`frēt gä`lə), 1812–1910, German astronomer.
..... Click the link for more information. in 1846. After much controversy both Adams and Leverrier were honored as responsible for the planet's discovery. In 1854, Leverrier became director of the Paris Observatory.