KH-10

The KH-10 (BYEMAN codename DORIAN) was the classified designation for the reconnaissance mission and equipment of the experimental Manned Orbiting Laboratory (MOL).

The system's mission was optical (regarding the presence of the mirrors), but also had a secondary signals intelligence collection mission.

The NRO announced formal guidelines for its covert studies, being performed under the code name "DORIAN." It stated that the studies and any subsequent hardware activities which were directed toward development of "an actual reconnaissance capability for the Department of Defense's manned orbiting laboratory....are under the sole direction and control of the National Reconnaissance Office and are part of the' National Reconnaissance Program." Normal military security would apply to other MOL study activities conducted outside Project DORIAN.

A single, unmanned launch of a simulated MOL which was a Titan I first stage oxidizer tank with the Gemini II capsule occurred in 1966. Subsequently the program was cancelled, and no additional hardware flew in space.

After DORIAN was cancelled, Project COLT provided six surplus 72-inch (1.8 m) optical mirrors to the Smithsonian Institution/University of Arizona's Multiple Mirror Telescope. The mirrors were constructed by Corning and used honeycombed borosilicate to reduce the weight.

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