Sir John Herschel, English astronomer, early 19th century.
© Science Museum / Science & Society Picture Library
Pencil drawing from a miniature. Sir John Herschel (1792-1871) the son of Sir William Herschel (1738-1822), who discovered the planet Uranus. Herschel followed his father in astronomical research, mapping the sky of the southern hemisphere and cataloguing many previously unseen stars. He was also a pioneer photographer, and coined the photographic terms 'negative and 'positive'.