Ritchey, George Willis (1864–1945)

US optical instrument maker and astronomer. He oversaw the construction of instruments at Chicago's Yerkes Observatory, where he adapted a 40-inch telescope to photography for George Ellery Hale in1896. After working with Hale in constructing the Mt Wilson Observatory 1904–09, he headed its optical shop 1909–19. In 1917 he photographed a nova that helped establish the existence of galaxies far from the Milky Way.

He was born in Tupper's Plains, Ohio. A onetime teacher of woodworking, he became an optical innovator. In later years he worked with the major observatory in Paris, France, where he solved a common mirror-distortion problem by collaborating on the design of the Ritchey-Chretien telescope with the US Naval Observatory in Washington, DC.