After 25 years of being adrift in space, an experimental satellite launched in 1974 has been rediscovered using tracking data from the U.S. Space Force.
The Infra-Red Calibration Balloon (S73-7) satellite was launched on April 10, 1974, as part of the United States Air Force’s Space Test Program. It was deployed from a larger satellite called the KH-9 Hexagon and was intended to act as a calibration target for remote sensing equipment. However, the satellite failed to inflate properly and drifted off into space.
The S73-7 satellite was rediscovered in April 2023, after it had been missing for 25 years. The satellite was found by Jonathan McDowell, an astrophysicist from the Harvard-Smithsonian Center for Astrophysics. McDowell searched through data archives and found that the satellite had gone off the grid from radar twice before, once in the 1970s and again in the 1990s.
The S73-7 satellite is now part of the large amount of space junk orbiting Earth. There are currently more than 20,000 objects in orbit around Earth, and it is becoming increasingly difficult to track them all. The U.S. Space Force is responsible for tracking objects in orbit and ensuring that they do not pose a threat to other satellites or spacecraft.
The rediscovery of the S73-7 satellite is a reminder of the challenges of space exploration. It is also a reminder of the importance of tracking space junk and ensuring that it does not pose a threat to other satellites or spacecraft.
