Some space junk just got smacked by more space junk, complicating cleanup

The European Space Agency hopes to demonstrate space junk removal in 2026—but now they have to recalibrate after their target got hit with debris.
Illustration of trackable objects orbiting Earth
It's even more cluttered up there than it looks. ESA

Having already done a decent job of it here on Earth, humans are well on their way to polluting the skies just beyond our atmosphere. After nearly 70 years of modern rocketry and satellite projects, there are literally millions of centimeter-and-larger discarded objects orbiting the planet—alongside an estimated 130 million tinier bits of space trash. Cleaning up all that debris is already presenting a challenge for experts and legislatorsReportedly, it’s gotten so bad that pilot projects can’t even get off the ground without being forced to recalibrate their objectives.

According to the European Space Agency working alongside Swiss startup ClearSpace, project planners will need to alter their proof-of-concept “derelict object” removal mission currently scheduled for 2026. The reason? It appears the space junk intended for capture and controlled deorbiting has been hit by another piece of space junk. ESA and ClearSpace representatives estimate the most likely cause is a “hypervelocity impact of a small, untracked object” that slammed into their 113kg, two-meter-wide rocket debris target first jettisoned during a 2013 ESA mission. Although the collision appears to have resulted in a “low-energy release of new fragments,” the team’s preliminary assessment indicates a “negligible” increase in collision risks for future missions.

[Related: “How harpoons, magnets, and ion blasts could help us clean up space junk.”]

The ClearSpace-1 mission team is currently continuing as planned as more data is collected on their slightly banged-up target, while a full analysis isn’t expected for at least “several weeks.” Until then, ClearSpace and the ESA are treating the new complication as a fine example of why such projects are already so necessary.

“This fragmentation event underlines the relevance of the ClearSpace-1 mission. The most significant threat posed by larger objects of space debris is that they fragment into clouds of smaller objects that can each cause significant damage to active satellites,” ESA reps explained. “To minimize the number of fragmentation events, we must urgently reduce the creation of new space debris and begin actively mitigating the impact of existing objects.”

As Universe Today also notes, fast-tracking these projects is incredibly important in order to avoid what is known as the “Kessler cascade” or “Kessler syndrome.” In these scenarios, the orbital space above Earth becomes so junky that debris collisions are essentially impossible to avoid, thus producing more debris, which begets more collisions, and so forth. Like our other pollution-based problems here on Earth, it’s difficult to estimate a time frame for an exact tipping point—but suffice to say, agencies like the ESA will know it when they see it. Barring additional orbital shenanigans, here’s to hoping projects like ClearSpace-1 will achieve their goals and get much-needed space cleanup underway.

Update August 25, 2023 9:17am: In a statement provided to PopSci, P.J. Blount, Cardiff University law lecturer and executive secretary for the International Institute of Space Law wrote:

“Space debris is an increasing problem that puts the benefits we receive from space at risk. Reducing the overall amount of debris will be critical to avoiding the onset Kessler syndrome. This will need to be a global effort, which will require coordination and cooperation of the major space powers. In the near term, it is unlikely that we will see new international law emerge to help address this issue. National level legislation, might help to alleviate some pressures operators face but will not be able to sufficiently address the debris problem without a global effort.”