LONDON, July 14 — Astronomers have identified a previously undetected population of space debris in geosynchronous orbit, the orbital band some 35,786 kilometres above Earth that hosts hundreds of the world’s most valuable satellites. The finding, confirmed by the U.S. Space Surveillance Network and optical telescopes in Chile and Australia, adds a new layer of risk to an already crowded neighbourhood. Geosynchronous orbit, or GEO, is prized because satellites there maintain a fixed position relative to the ground, making them indispensable for communications, weather monitoring and national security.
The newly spotted swarm ranges from tiny fragments to larger defunct objects. According to the European Space Agency’s Space Debris Office, as of January 2024 there were an estimated 36,500 objects larger than 10 centimetres in orbit around Earth, along with millions of smaller pieces.
The U.S. Space Force tracks objects in orbit but cannot detect debris smaller than about 10 centimetres, meaning much of this new population may have gone unnoticed for years. The debris likely originates from past satellite breakups. Two events stand out: the 2009 collision between Iridium 33 and Cosmos 2251, and the 2007 Chinese anti-satellite test, which deliberately destroyed a Chinese weather satellite and created one of the largest debris clouds in history.
The Kessler Syndrome threat
Without active removal, the debris population could grow exponentially through a cascade of collisions known as the Kessler Syndrome, a scenario first predicted by NASA scientist Donald J. Kessler in 1978. Each collision creates more fragments, which in turn increase the likelihood of further collisions.
GEO, unlike low Earth orbit, has no natural cleaning mechanism — debris there can remain for centuries. The salient point, for all the noise about rocket launches and satellite constellations, is that nobody is currently removing anything from GEO.
The orbit is effectively a junkyard with no bin collectors.
Security and sustainability
The growing debris field threatens the long-term sustainability of an orbital zone that underpins modern life. Communications networks, financial trading systems, military early-warning satellites and weather forecasting all rely on spacecraft in geosynchronous orbit. A catastrophic collision could disable multiple satellites at once, with consequences felt on the ground.
The U.S. Space Force maintains a catalogue of tracked objects, but its sensors have limits. The newly detected population was only spotted through a coordinated effort combining American surveillance networks with ground-based optical telescopes in the Southern Hemisphere, suggesting that further undetected debris may still be out there.
For now, the international community has no binding agreement on debris removal. The U.S. administration under President Donald Trump has emphasised space security, but active remediation remains technically difficult and politically sensitive. The 2007 Chinese anti-satellite test, which contributed to the debris now being found, remains a point of tension in bilateral space relations.
What to watch next: whether the newly identified debris triggers any revision in collision-avoidance procedures for GEO satellites, and whether any government or commercial entity steps forward with a credible plan to clean up an orbit that has, it would seem, no natural way of cleaning itself.
