James Challis

James Challis (1803 to 1882) was an English clergyman, physicist and astronomer, born in Braintree, Essex, where his father was a stonemason. He graduated from Trinity College, Cambridge, in 1825 as Senior Wrangler and first Smith's prizeman, was elected a fellow of Trinity in 1826 and was ordained in 1830, holding the benefice of Papworth Everard until 1852. He resigned his fellowship on marrying in 1831. In 1836 he became director of the Cambridge Observatory and Plumian Professor of Astronomy and Experimental Philosophy, holding the chair until his death. He lectured in all areas of physics and, as examiner for the Smith's prize, appraised the early work of men such as G. G. Stokes, Arthur Cayley, John Couch Adams, William Thomson and James Clerk Maxwell, and he disagreed for over a decade with Stokes's conclusions. He investigated a wide range of physical phenomena but made few lasting contributions outside astronomy, and he is best remembered for his missed opportunity to discover the planet Neptune in 1846.