The original MMT was the Multiple-Mirror Telescope, which used mirrors left over when the Pentagon canceled the Manned Orbiting Laboratory. (credit: MMT Observatory) Through the looking glass

The Manned Orbiting Laboratory (MOL) was expensive, especially for a military space program that was already expanding rapidly in the 1960s while the Vietnam War was ramping up. Although nowhere near as pricey as Apollo, MOL was still a substantial expenditure, involving the procurement of a major optical system, human spaceflight systems—including Gemini spacecraft—and new large rockets to boost MOL into orbit. By the time it was canceled in summer 1969, MOL’s price tag had doubled to more than $3 billion, and its schedule had repeatedly slipped. When it was canceled, program officials sought out potential customers of the MOL hardware that had already been built. MOL officials within the secret National Reconnaissance Office that was responsible for it made inquiries to NASA offering their hardware and large optics technology, trying to make lemonade out of the lemons of the cancellation decision. Among the most expensive and unique pieces of MOL hardware were more than half a dozen large mirrors that were a key component in MOL’s large KH-10 DORIAN camera system. MOL officials within the NRO made inquiries to NASA offering their hardware and large optics technology, trying to make lemonade out of the lemons of the cancellation decision. In June 1969, the Director of the National Reconnaissance Office wrote a memorandum to the Secretary of the Air Force indicating that the MOL program was canceled, but that work could continue on “those camera system elements useful for incorporation into an unmanned satellite system optimized to use the Titan IIID.” Because the DORIAN camera system was developed under a covert contract, its continuation was also covert. By late June, Secretary of the Air Force Robert Seamans, who had previously been at NASA, ordered the creation of an ad hoc group to identify MOL hardware that might be useful to the Defense Department and/or NASA. This included test and checkout equipment and technology. Seamans also directed that the group identify work that might be continued in other Air Force projects and desirable MOL technology that might be continued. In early September, NASA Associate Administrator Homer E. Newell wrote two letters to Seamans. In one letter, Newell explained that NASA had an active space astronomy program that could possibly make use of the MOL equipment and technology. He noted that Aden Meinel of the University of Arizona and two representatives from NASA’s Marshall Space Flight Center examined the MOL hardware at Eastman Kodak “to make a preliminary evaluation as to the suitability of this equipment for stellar astronomy, the steps that might be required to so modify it, and the probable compatibility of the system with the Apollo Telescope Mount and dry workshop.” The men were expected to report back within several weeks. Newell wrote that if the report was positive, NASA would like a detailed technical feasibility study undertaken in secret. However, only if the results were sufficiently good to lead to a recommendation to use the hardware would NASA then seek to discuss how to address the thorny classification issues associated with the technology and contracts. Newell’s second letter concerned the possible use of the MOL Acquisition and Tracking System and its simulator for NASA programs. This system was to be used by the MOL astronauts to spot targets on the ground and cue the big DORIAN camera system to photograph them. According to other declassified documents, there was serious discussion about NASA using this system, although ultimately the agency decided it would not be useful. In September 1969 MOL officials were also involved in discussions about use of MOL camera equipment in a program known as “Eight Card” for the Air Force Special Weapons Center, responsible for ensuring that Air Force aircraft could carry nuclear weapons. A short time later the NASA review of MOL hardware was complete and, according to Samuel Hubbard, a technical advisor on MOL, the NASA team had determined that the technology and facilities at the MOL contractors would indeed be useful to NASA. The question was how best to keep the contractors sufficiently active so that when NASA made final decisions on future space-based telescopes they would not have to re-learn how to make large space-qualified optics. Apparently the NRO had recently learned the hard way (meaning expensively) that Kodak’s large optics manufacturing skills had atrophied between programs. Hubbard indicated that NASA was interested in possible future large optical telescopes with diameters of two and three meters. He stated that NASA was considering a two-meter telescope for inclusion in the second Skylab orbital workshop. The first Skylab would focus on Earth and solar studies, but NASA was considering having the second Skylab conduct astronomy. Hubbard did not indicate that NASA wanted the leftover MOL mirrors; the agency was primarily interested in the technology used to manufacture them. NASA never flew the second Skylab orbital workshop. It now resides in the Smithsonian’s National Air and Space Museum. It took NASA many years to commit to a large astronomical telescope, which eventually became the Hubble Space Telescope. But declassified MOL documents indicate that NASA did undertake more detailed studies of MOL optical technology. This relationship may have continued, but the NASA-NRO relationship during the early years of Hubble development remains classified. In September 1969 MOL officials were also involved in discussions about use of MOL camera equipment in a program known as “Eight Card” for the Air Force Special Weapons Center. AFSWC was responsible for ensuring that Air Force aircraft could carry nuclear weapons. A MOL official stated, “much of the technology associated with pointing, tracking, command and control, image velocity sensing, manufacturing and testing of bearings, torquers, encoders, etc., has a direct application to Eight Card.” But one key issue to resolve was that some of the equipment was unclassified and some of it was classified, including the contracts to manufacture it, so even putting some potential customers in contact with the contractors presented problems. Unfortunately, there is no further information on what “Eight Card” actually was, or if it eventually used existing MOL hardware. NASA did express interest in some other MOL hardware, such as life support equipment and the MOL waste management system—i.e., the toilet. Because some of the MOL camera equipment took a long time to manufacture, it had started production early and was in an advanced state when the project had been canceled. It was then placed in storage. But the sophisticated optics hardware was not applicable to current NASA missions. Although MOL was supposed to orbit the Earth looking down, its greatest success was sitting on Earth looking up. Although the MOL optical hardware did not get into space, it did have an interesting second life. A January 1971 memo to NRO Director John McLucas referred to “Project COLT.” COLT was a proposal by Aden Meinel of the University of Arizona, who had earlier been asked by NASA to evaluate the MOL technology for space use. Meinel had come up with an idea to incorporate six 72-inch (1.8-meter) DORIAN “blanks”—reflecting mirrors—into a ground-based astronomy telescope. NRO officials were intrigued by Meinel’s proposal. According to the declassified memo, Project COLT had several advantages, but two of them remain deleted for security purposes. One advantage that is not deleted is, “Utilization of salvaged DORIAN blanks permits construction of a large aperture system at reduced cost.” The deleted sentences may refer to the fact that the NRO would learn about how to develop multiple mirror optical systems that later became common for ground-based astrophysical observatories. COLT eventually led to the University of Arizona’s Multiple-Mirror Telescope (MMT), which was built atop a mountain near Tucson, Arizona, and was in service for nearly two decades before it was replaced with a single monolithic mirror that kept the MMT acronym. The DORIAN blanks had to be re-shaped to be useful for ground-based astronomy. When they were eventually replaced, the mirrors were put in a storage facility at the base of the mountain. In the late 2000s there was a proposal by astronomers to incorporate some of the DORIAN mirrors into new dual-mirror telescope mounts and use them in the search for potentially hazardous asteroids. But this proposal has not been funded. The full story of Project COLT and how the formerly top secret mirrors were extracted from the national security world to be used for a ground-based astronomy program remains to be told. But it is an important aspect of the MOL legacy. Although MOL was supposed to orbit the Earth looking down, its greatest success was sitting on Earth looking up. Home









