A quarter century after it was lost in orbit an American military test satellite has been rediscovered
A target satellite launched in 1974 as part of a military test of its surveillance satellite technology has been rediscovered in orbit twenty-five years after it was last tracked.
The Infra-Red Calibration Balloon (S73-7) satellite started its journey into the great unknown after launching on April 10, 1974 through the United States Air Force’s Space Test Program. It was originally contained in what was called “The Hexagon System” in which S73-7, the smaller satellite, was deployed from the larger KH-9 Hexagon once in space. S73-7 measured 26 inches wide (66 centimeters) and began its life heading into a 500 mile (800 kilometers) circular orbit.
While in orbit, the original plan was for S73-7 to inflate and take on the role as a calibration target for remote sensing equipment. After this failed to be achieved during deployment, the satellite faded away into the abyss and joined the graveyard of unwanted space junk until it was rediscovered in April.
After it first drifted out of contact after launch in 1974 S73-7 has been been lost and rediscovered several times, first in the 1970s, then in the 1990s, and now. It appears its radar profile makes it hard to pick up, which means it will likely be lost again.
A target satellite launched in 1974 as part of a military test of its surveillance satellite technology has been rediscovered in orbit twenty-five years after it was last tracked.
The Infra-Red Calibration Balloon (S73-7) satellite started its journey into the great unknown after launching on April 10, 1974 through the United States Air Force’s Space Test Program. It was originally contained in what was called “The Hexagon System” in which S73-7, the smaller satellite, was deployed from the larger KH-9 Hexagon once in space. S73-7 measured 26 inches wide (66 centimeters) and began its life heading into a 500 mile (800 kilometers) circular orbit.
While in orbit, the original plan was for S73-7 to inflate and take on the role as a calibration target for remote sensing equipment. After this failed to be achieved during deployment, the satellite faded away into the abyss and joined the graveyard of unwanted space junk until it was rediscovered in April.
After it first drifted out of contact after launch in 1974 S73-7 has been been lost and rediscovered several times, first in the 1970s, then in the 1990s, and now. It appears its radar profile makes it hard to pick up, which means it will likely be lost again.