John Couch Adams

When John Couch Adams was growing up in Cornwall, he received little formal instruction in math. Instead, he learned the subject on his own. And when he saw Comet Halley in 1835, he decided to apply his math skills to calculating the motions of heavenly bodies. And a decade later, he calculated the motions of something that no one had ever seen: Neptune, the Sun’s farthest major planet.

Adams was born 200 years ago this week. He was the son of a poor farmer. But he was able to attend Cambridge University, where he earned a degree in mathematics.

By then, he’d heard about a problem with the orbit of Uranus, the seventh planet from the Sun. It didn’t match predictions based on Isaac Newton’s laws of gravity. The leading idea said the giant planet was being tugged at by another world farther from the Sun.

Adams set to work on the problem, and calculated where the planet should be found. British astronomers delayed in searching for the new world, though. In the meantime, French astronomer Urbain le Verrier had made the same calculations. The director of Berlin Observatory agreed to look for the planet, and quickly found it.

Despite some controversy, astronomers decided to credit both le Verrier and Adams for discovering the new planet — by calculation, not observation.

Adams later became director of Cambridge Observatory, where he spent the final three decades of his life — studying the intricate motions of the heavens.

Script by Damond Benningfield