Object Details
Designer
George Willis Ritchey
Manufacturer
Yerkes Observatory
Summary
George Willis Ritchey built this mirror grinding machine at the Yerkes Observatory in Williams Bay, Wisconsin, in the late 1890s. Under the sponsorship of George Ellery Hale, it was used to grind a series of telescope mirrors starting with a 60-inch mirror for a telescope initially intended for Yerkes. The grinding machine was moved to Pasadena in 1904 to complete work on the 60-inch mirror. The apparatus was later transferred to the California Institute of Technology, which sold it to the Lick Observatory of the University of California in 1949. It was used for making numerous mirrors over the next four decades and was extensively modified. It embodies the "sub-diameter tool" design approach to making large telescope mirrors: the grinding tool is drawn across the mirror blank by programmable rotating arms.
It was donated to NASM by the Lick Observatory in 1993 and shipped in March of that year.
Alternate Name
Ritchey Mirror Grinding Machine
Credit Line
Gift of the Lick Observatory, University of California
Inventory Number
A19930093000
Restrictions & Rights
Usage conditions apply
Type
INSTRUMENTS-Scientific
Materials
Wood and iron construction, leather belts, steel hardware
Dimensions
3-D: 274.3 x 365.8 x 243.8cm (108 in. x 12 ft. x 96 in.)
Country of Origin
United States of America
See more items in
National Air and Space Museum Collection
Location
Steven F. Udvar-Hazy Center in Chantilly, VA
Exhibit Station
Space Science
Data Source
National Air and Space Museum
Link to Original Record
Record ID
nasm_A19930093000