The satellites were made available by the Smithsonian National Air and Space Museum's Udvar-Hazy Center at Dulles Airport, Va. Despite the small window of opportunity to see the spy satellites crowds lined up to catch a glimpse of what was at the time cutting edge technology.
The satellites were used to capture high resolution images of Soviet-era missile silos, submarines and anything else deemed worthy of investigation by the U.S. military.
Interestingly enough some engineers speculate the technology used to develop these satellites may have later been used to advance designs of the Hubble Space Telescope.
Military space historian Dwayne A. Day was exuberant after his first look at the KH-9 HEXAGON.
"This was some bad-ass technology," Day told SPACE.com. "The Russians didn't have anything like it."
Day, co-editor of "Eye in the Sky: The Story of the CoronaSpy Satellites," noted that "it took the Soviets on average five to 10 years to catch up during the Cold War, and in many cases they never really matched American capabilities."
Phil Presser, designer of the HEXAGON's panoramic 'optical bar' imaging cameras, agreed with Day's assessment.
"This is still the most complicated system we've ever put into orbit …Period."
The HEXAGON's twin optical bar panoramic mirror cameras rotated as the swept back and forth as the satellite flew over Earth, a process that intelligence officials referred to as "mowing the lawn."
Each 6-inch wide frame of HEXAGON film capturing a wide swath of terrain covering 370 nautical miles — the distance from Cincinnati to Washington — on each pass over the former Soviet Union and China. The satellites had a resolution of about 2 to 3 feet (0.6 to nearly 1 meter), according to the NRO. [10 Ways the Government Watches You]
According to documents released by the NRO, each HEXAGON satellite mission lasted about 124 days, with the satellite launching four film return capsules that could send its photos back to Earth. An aircraft would catch the return capsule in mid-air by snagging its parachute following the canister's re-entry.
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