This is a lens from an index camera used from 1962-1972 onboard the U.S. Corona photoreconnaissance satellites. Index cameras took a small scale photograph of the area being covered by the main panoramic cameras and, in conjuction with imagery from the horizon cameras and stellar camera, enabled photo interpreters to more easily determine the exact terrain being photographed by the main cameras. This unflown lens was manufactured by Graflex, Inc. and donated by Hughes Danbury Optical Systems to NASM in 1996.
This object is on display in James S. McDonnell Space Hangar at the Steven F. Udvar-Hazy Center in Chantilly, VA.