Overview

The planet Neptune was discovered in 1846 following laborious calculations by Englishman John Couch Adams (1819-1892) and Frenchman Urbain Leverrier (1811-1877). These astronomers, attempting to explain deviations noted in the orbit of Uranus, independently and nearly simultaneously predicted the location of Neptune, which was then located with little trouble by German astronomer Johann Gottfried Galle (1812-1910). This discovery was viewed as a triumph of mathematics and physics, winning acclaim for both Adams and Leverrier.

Background

Through most of human history mankind lived in a solar system with seven "planets"—Mercury, Venus, the Moon, Mars, Jupiter, Saturn, and the Sun—that revolved around the Earth. The work of Galileo (1564-1642) and Nicolaus Copernicus (1473-1543) showed this notion to be false, but the Copernican solar system still ended at the orbit of Saturn until William Herschel...