John Herschel (1792-1871), British astronomer and chemist. John Frederick William Herschel was born in Slough, England, and educated at the University of Cambridge. He reexamined the double stars and nebulas observed by his father, Sir William Herschel, and added to the elder Herschel's catalogs. To complete his father's survey of the heavens, he led an expedition to the Cape of Good Hope in 1834 to study the stars of the southern hemisphere. The results of his expedition were published in 1847. Herschel also made important contributions to the field of photography: In 1839 he developed a chemical fixing solution, commonly called a hypo, that fixed an image on photosensitive paper and made the paper insensitive to further exposure. Herschel became president of the Royal Astronomical Society in 1848. He was knighted in 1831 and was created baron in 1850.