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	Urbain Jean Joseph Le Verrier
	Le Verrier was an astronomer who discovered the planet Neptune by using math!

Urbain Jean Joseph Le Verrier was born in 1811 at Saint-Lô, France. He was a teacher of astronomy at the Ecole Polytechnic Paris. Le Verrier studied the planets Mercury and Uranus. He noticed both planets had unusual motions. Le Verrier thought an asteroid belt between Mercury and the Sun caused Mercury's unusual motion. We now know this was incorrect. He thought the unusual motion of Uranus was due to another planet that had not yet been discovered. Le Verrier used math to calculate where to find the new planet. A fellow astronomer, Johann Gottfried Galle, observed the planet where Le Verrier's calculations said it would be. The planet was named Neptune. Le Verrier shares the honor as the discoverer of Neptune with John Couch Adams. Adams completed his calculations only a few months before Le Verrier.

In 1854, Le Verrier became the director of the Observatory of Paris. He worked very hard to make the observatory a place where good scientific work was done. Urbain Jean Joseph Le Verrier died in Paris in 1877.

A Question True or False? Le Verrier used a telescope to discover Neptune.