Lewis Rutherfurd was an American astronomer who invented photographic telescopes and helped to establish the field of astrophysics. He became interested in astronomy and physics while he was a student at Williams College. However, upon his graduation in 1834, he studied law and joined the partnership of a New York law firm. Throughout the years of his legal practice, Rutherfurd continued to pursue astronomy during his leisure with an observatory he built on his own property.
Rutherfurd retired from law and began to experiment with astronomical photography in 1858. He modified his telescope and outfitted his apparatus as a photographic spectroscope, which was then used to analyze the spectrum of light emitted by the Sun and other stars. Rutherfurd published his first paper in 1862, proposing that the difference in visual spectra emitted by stars might correspond with a difference in their composition.
Rutherfurd continued to evolve his telescope designs, engineering models that took increasingly clear pictures, were calibrated for measurement, and captured on film stars that had previously been too faint to record. When he retired in 1877, Rutherfurd donated his apparatus, telescope, and photographic plates to the observatory at Columbia College, which is now Columbia University.
Rutherfurd was a charter member of the National Academy of Sciences and a trustee of Columbia College.