US spectroscopist and astronomical photographer. He produced a classification scheme of stars based on their spectra that turned out to be similar to that of Italian astronomer Angelo Secchi.
Rutherfurd was born in Morrisania, New York, and studied at Williams College, Massachusetts. In 1856 he had his own observatory built and spent the rest of his life working there.
From 1858 Rutherfurd produced many photographs that were widely admired of the Moon, Jupiter, Saturn, the Sun, and stars down to the fifth magnitude. He went on to map the heavens by photographing star clusters, and devised a new micrometer that could measure the distances between stars more accurately.
In 1862 he began to make spectroscopic studies of the Sun, Moon, Jupiter, Mars, and 16 fixed stars. To help this work, Rutherfurd devised highly sophisticated diffraction gratings.