A satellite called Infra-Red Calibration Balloon (S73-7) that was launched in 1974 to be a calibration target for remote sensing equipment has been rediscovered after orbiting undetected for 25 years.
The satellite got separated from its parent spacecraft after launch but failed to inflate as intended. It then orbited in space anonymously for decades.
Astrophysicist Jonathan McDowell studied radar data archives and discovered the satellite disappeared from radar twice before – in the 1970s and 1990s, likely due to its small size and material not being metallic.
With over 20,000 objects in space currently, it is difficult to continuously track each one, especially small objects. Ground sensors can detect objects but matching them precisely requires correlating location data over time.
The rediscovery of this lost satellite after 25 years is helpful for those working to catalog and track the thousands of human objects in space, though challenges will increase as satellite deployments grow. Maintaining awareness of what is in orbit supports safety and sustainability of space activities.
Source: Space
