Lost in Orbit: The Rediscovery of S73-7 Brings Focus to Space Junk Tracking Challenges

The discovery of the lost satellite S73-7, originally launched in 1974 by the US Air Force Space Test Program, has brought new attention to the challenges of tracking objects in orbit. According to astrophysicist Jonathan McDowell, the satellite disappeared from radar twice, once in the 1970s and once in the 1990s. With over 20,000 objects currently in orbit, tracking space junk is no easy task.

Ground-based radar and optical sensors help identify these objects, but identifying each one remains difficult due to their large number. Engineers can monitor a satellite’s progress based on its original path and altitude, but deviations from the plan or drifts can make finding it again a challenge. This makes rediscovering lost satellites like S73-7 a significant success in improving our knowledge of what is in orbit around Earth.

However, as more satellites are launched into space, understanding what is already there and potential threats will become increasingly difficult. The goal is to do the best possible job of tracking objects in space and McDowell explains that missing a few objects may not pose a significant risk but it’s crucial to continue to improve our knowledge of what is out there. The discovery of S73-7 is just one step towards achieving this goal.