Space debris rendering. Credit: Adobe stock

Space Traffic Management (STM) — the identification and deconfliction of potential mission-terminating collisions for operational spacecraft — has gained attention as the population of operational satellites in low Earth orbit has dramatically increased.

Operational satellites and their supporting infrastructure must be resilient and responsive to mitigate mission-ending or catastrophic collisions to maintain a safe and robust space industry. We applaud the efforts of organizations and policymakers to develop, synchronize, and refine STM principles, including data sharing, state vector accuracy improvement, near-real-time conjunction data messages, and expanding global space surveillance assets.

However, STM alone is insufficient to guarantee safe space operations. Space Debris Management (SDM) — the mitigation and remediation of space debris, including fragments and massive derelict objects — must be pursued with even more urgency than STM.

Micrometeoroids and orbital debris are increasingly cited as the cause of satellite anomalies. We can reduce the orbital debris side of the problem by eliminating the objects most likely to be involved in a collision. Our recent LEO Collision Risk Continuum paper reinforced that debris-on-debris conjunctions have a greater debris-generating potential than STM encounters (i.e., operational satellites against all resident space objects). Many thousands of massive derelict objects — defunct payloads and abandoned rocket bodies — have been left in similar orbits. These clusters of massive derelicts, along with large amounts of fragmentation debris, make large debris-generating collisions more likely at distinct altitudes. Specifically, our analysis identified the most likely collisions to be between spent Russian rocket bodies and Chinese and American debris fragments and non-operational payloads. These collisions are most likely to occur between 775 and 850 kilometers, making it the highest priority region for reducing the debris-generating potential.

This situation presents a unique opportunity for collaboration among the leading spacefaring nations to demonstrate the viability of active debris removal (ADR) and kick-start the commercial ADR industry.

The U.S., Russian, and Chinese space agencies (NASA, Roscosmos, CNSA) should initiate a joint remediation mission to Space Debris Management is even more urgent than Space Traffic Management remove 20 of the statistically-most-concerning objects in LEO. The European, Japanese, and United Kingdom space agencies (ESA, JAXA, and UKSA) have already been trailblazers in this quest by mobilizing ClearSpace and Astroscale to perform ADR technology demonstrations. Examples of other technologies that have benefited from government support over the decades include satellite communications (Intelsat, Inmarsat), Earth observation (Landsat, SPOT), and SAR (Seasat, Radarsat).

ADR is environmental protection — the space environment is home to vital capabilities to support such humanitarian endeavors as greenhouse gas monitoring, natural resource management, wildfire detection, and food security. The proliferation of operational satellites — and, indeed, collision risk — will only increase without timely intervention to remove decades-old massive derelicts. Simply saying that the problem is “too complex” ignores the warning signs. Humans are messy — we wait until a catastrophe occurs before we take the action that we know is needed. A marathon begins with the first step; let’s get started.


Darren McKnight is senior technical fellow at LeoLabs. He is responsible for space risk algorithm development, space incident investigations, and customer support to space operators. Chris Kunstadter is global head of space at AXA XL, a division of AXA. Chris manages the space insurance portfolio and is actively involved in all aspects of AXA XL’s space activity, including technical, financial, and actuarial analysis, coverage design, claims handling, industry outreach, and business development.

This article originally appeared in the February 2022 issue of SpaceNews magazine.