Main Page | See live article | Alphabetical index John Frederick William Herschel (March 7, 1792 - May 11, 1871) was an english mathematician and astronomer. He was the son of astronomer William Herschel. John Herschel originated the use of the Julian day system in astronomy and made several important contribution to the improvement of photographic processes (Cyanotype). External link http://www-groups.dcs.st-and.ac.uk/~history/Mathematicians/Herschel.html This article is from Wikipedia. All text is available under the terms of the GNU Free Documentation License.