Nearly 40 years ago, even their existence was top secret. But in two days thousands of spy satellite images will be posted on the Web for all the world to see — and download.
In a move that has surprised but pleased researchers, the National Imagery and Mapping Agency (NIMA) has released a trove of about 50,000 images snapped during the 1960s, '70s and '80s by two U.S. spy satellites.
Historians hope to use the pictures to settle long-standing questions about capabilities and alliances during the Cold War while scientists want to use them to track biological changes on Earth and possibly plot the course of global warming.
"I was very surprised they decided to release them," said Jeffrey Richelson, a researcher with the nonprofit organization National Security Archives and author of the book America's Secret Eyes in Space. "Their release was a bigger secret than the war plan."
Caught in a Bucket
Former President Bill Clinton and Vice President Al Gore first launched the initiative to release declassified images to the scientific community in 1991 and the first batch of satellite images were unveiled in 1995. That first collection included 860,000 images from the once-secret CORONA satellite and offered overhead swatches of the Earth's surface between 1960 and 1972.
Some feared the recent terrorist attacks and ongoing war against terrorism might discourage the current administration from continuing the program. But as Tim Brown, a military analyst for the nonprofit Global Security, Inc., said, "It seems they were just on autopilot and were going to release them anyway."
Run under the code name "GAMBIT," the KH-7 surveillance satellite orbited Earth between 1963 and 1967 and captured images detailed enough to pick out objects only 2 feet to 4 feet wide on the ground. The second satellite, KH-9, which orbited between 1973 and 1980, was mainly for mapping, so its view was more sweeping with an average resolution of 20 feet to 30 feet.
Unlike today's satellites that relay their images by digital transmission, the two Cold War-era satellites returned their film in buckets. As the buckets sailed down to Earth by parachute, specially designed aircraft caught them and delivered them to Secret Service agents.
"We talk about the tremendous achievement of the space race — that was all very public," said John Newman, a historian at the University of Maryland University College who previously served in military intelligence and on the National Security Council staff. "All those people got the glory, but the people who did this had to stay in the closet. Now they have their day."
Global Warming Tool
It's not yet known (by most) exactly what the batch of pictures will reveal when they're released to the U.S. Geological Survey Web site http://www.usgs.gov/features/satellite_images.html on Nov. 15. But a preview sample released to the public in October show black-and-white shots of locations including a shipyard in Siberia, the Eiffel Tower in Paris and overhead views of Moscow, Hanoi, and Beijing.
If the sampling is a good indication of the rest, the images could be a boon for environmental researchers.
"The No. 1 value is going to be environmental," said Bob Vincent, a geology professor at Bowling Green State University in Ohio and director of a NASA-funded project to make satellite data more available to universities. "The data are very very important to document how this planet has changed."
There are countless ways scientists can glean information from the old pictures. One is by detecting subtle changes in terrain. For example, an overhead glimpse of Siberia in 1963 might reveal the latitudes where tundra remained frozen year round. Those latitudes can then be compared with current photos to see if they have retreated, which would be a sign of warming.
"If we can document where the changes are and the world can agree those changes are greater than we like, then we can collectively make a decision to do something about global warming," said Vincent.
Biologists can also use the images to take inventory of changes in the natural landscape, such as the takeover of a particular kind of tree in a given region. Archaeologists can use them to spot telling features such as clear lines of younger vegetation, indicating where ancient people once trod down trails.
Hidden History Lessons
Newman hopes to use the images to answer some long-standing questions in history. For example, spy satellite pictures over China could shed light on the extent of cooperation between China and the Soviet Union during the Vietnam War.
"We might be able to see things like Soviet equipment on Chinese rail lines," he said. "I'm very curious about the role of those rail lines during the war."
The images also offer unique insight into U.S. leadership during the Cold War. As former Sen. Bob Kerrey, D-Neb., remarked at a recent conference about the images in Maryland, there are lessons to be learned in "knowledge of the differential between how our leaders interpreted these images and how they're interpreted today."
Some argue there is value alone in making something that was once secret, public.
"It's terribly significant, especially in today's climate," said Newman. "It delivers on the promise that an open democracy does not keep anything under wraps unless it needs to be. It says great things about our system of government."