PARIS, July 14 — Against this backdrop of a rapidly filling orbital environment, the question of what happens when space simply runs out of room is no longer theoretical. The growing congestion above our heads, particularly in the geostationary orbit that hosts Europe’s Galileo navigation satellites, has pushed debris mitigation from a technical niche into a pressing geopolitical concern. The discovery of a hidden swarm of debris in GEO in 2023 has sharpened the focus.
For operators of GPS, Russia’s GLONASS, and Europe’s own Galileo constellation, the risk of collision has risen measurably. What is at stake is not just expensive hardware, but the integrity of navigation, timing, and communications systems that underpin modern life on the continent.
In the corridors of the European Space Agency and national space agencies, the conversation has shifted from whether to act to how quickly.
Rules of the Road, Old and New
The regulatory landscape is a patchwork. The U.S. Federal Communications Commission, in 2022, imposed a firm rule: satellite operators must deorbit or move their spacecraft to a graveyard orbit within five years of the end of a mission. That graveyard orbit sits 300 kilometres above the GEO belt, a deliberate buffer zone to keep dead satellites from interfering with active ones.
On a broader international scale, the Inter-Agency Space Debris Coordination Committee, known as the IADC, recommends a 25-year rule for deorbiting satellites in low Earth orbit. It is a guideline, not a binding treaty, and compliance varies.
Against this backdrop, the United Nations Office for Outer Space Affairs continues to promote international guidelines, though enforcement remains elusive. The wider picture includes U.S. Space Policy Directive-3, issued in 2018, which lays out a national framework for space traffic management. That directive, alongside the conjunction warnings provided by the U.S. Space Command to satellite operators worldwide, forms the backbone of current collision avoidance.
But warnings alone do not remove debris.
Active Removal: A European First
The most concrete step toward cleaning up what is already there comes from Europe. The European Space Agency’s ClearSpace-1 mission, planned for 2026, is designed to capture a 100-kilogram payload adapter left in orbit. It represents the first attempt at active debris removal, a technology that has been under development for years but has yet to be demonstrated in a real operational context.
The mission is emblematic of a shift in thinking. For decades, the focus was on prevention: design satellites to minimise debris, follow post-mission disposal guidelines, and hope the worst does not happen.
That approach, while necessary, is no longer sufficient. The accumulation of fragments, defunct spacecraft, and discarded hardware has reached a point where removal must complement prevention.
The Kessler Syndrome Looming
Without decisive action, the scenario known as the Kessler Syndrome could render the geostationary orbit unusable within decades. In that cascade, a single collision generates debris that triggers further collisions, each one multiplying the hazard. The GEO belt, a finite and irreplaceable resource, would become a no-go zone.
For Europe, which relies on Galileo for sovereign navigation and timing, the implications are profound. The 2023 discovery of the hidden swarm in GEO was a warning shot.
It demonstrated that the debris population is not only larger than previously understood but also harder to track. The conjunction warnings from the U.S. Space Command are a stopgap, not a solution. What to watch next is the outcome of ClearSpace-1.
If it succeeds, it will open the door to a new industry of orbital cleanup. If it fails, the path forward becomes murkier.
Either way, the clock is running.
