Mount Hopkins, AZ
Smithsonian Institution, Multiple Mirror Telescope
Scope/Solutions
With the advent of economical large spun cast mirrors, the Smithsonian Institution and the University of Arizona wished to convert the Multiple Mirror Telescope (MMT) to a telescope with a single 6.5 m dia. mirror to retain its position as one of the world’s most powerful instruments. SGH developed the drawings and specifications for this modification.
Highlights of SGH’s work on this project include the following:
- Developed conversion concepts and the final designs of the new Optics Support Structure (OSS) and mirror cell structure
- Designed a system that allows for in-place aluminizing of the primary mirror by lifting in a vacuum head and using the mirror cell as the bottom part of vacuum chamber
- Designed the required modifications to the rotating observatory building to accommodate the larger OSS
Project Summary
Solutions
New Construction
Services
Advanced Analysis
Markets
Science & Defense
Client(s)
Harvard-Smithsonian Astrophysical Observatory
Key team members

Additional Projects
West
Sutro Tower
Since 2002, SGH has performed a wide range of engineering services, including seismic evaluation and upgrade, structural design of tower reconfiguration, annual inspection and repairs, and design of site work and addition of appurtenant structures.
West
Electronic Space Systems Corporation, Compact Range Reflector
SGH designed the structure and consulted on lifting procedures for the 75 ft dia. offset parabolic reflector.