Signedon metal label screwed to prism housing, but covered in gray paint: TELESCOPE - 20 X 120 / FIELD ANGLE 2.4° / MODIFIED ARMY M-17 / NWP - SAO / SERIAL NO. 906
Inscribedpart no. cast into tailpiece holding eyepiece: C78175
part no. cast into prism housing: D43785
part no. cast into light socket collar around eyepiece: B172949
scratched underneath the prism housing: 29741
Historical AttributesThis 5-inch aperture Apogee telescope was the type widely used for satellite tracking by Project Moonwatch of the Smithsonian Astrophysical Observatory. The telescope was was a modified Army M-17 elbow telescope with an aperture of 120mm, magnification of 20x, and field of view of 2.4°. Teams of volunteers, each armed with such a telescope backed up an optical network of 12 Baker-Nunn tracking cameras, which were put into operation in late 1957 and early 1958.
The label has this abbreviation: NWP - SAO. It may stand for Naval Warfare Publication - Security Assistance Organization; or Naval Warfare Publication - Smithsonian Astrophysical Observatory.
After Moonwatch, this particular Apogee telescope was repurposed as the finder telescope on the 8-inch Ross-Lundin astrograph at Oak Ridge Observatory in Harvard, Massachusetts.
ProvenanceOak Ridge Observatory, Building # 5 (8-inch Ross-Lundin astrograph mounted by Fecker); transferred to CHSI, August 2015.