What is Space Traffic Management?
Space Traffic Management (STM) refers to the set of technical measures, regulatory frameworks, and international agreements needed to manage the growing population of active satellites and debris in Earth orbit, coordinate manoeuvres, prevent collisions, and ensure the long-term sustainability of orbital operations. STM encompasses conjunction screening, collision avoidance warnings, manoeuvre coordination, orbital frequency coordination, and post-mission disposal enforcement.
Current state: no binding framework
Unlike aviation — which has ICAO (International Civil Aviation Organization) providing binding international air traffic control standards — space currently lacks an equivalent binding international STM authority. The US Space Surveillance Network (operated by USSPACECOM) tracks objects larger than 10 cm and provides conjunction data messages (CDMs) to satellite operators globally as a free service, but this is voluntary. National regulators (FCC, OFCOM, ARCEP) impose debris mitigation rules as conditions of licensing, creating a patchwork of national requirements.
Conjunction analysis and collision avoidance
Conjunction analysis compares predicted orbital trajectories for all catalogued objects and identifies 'conjunctions' — close approaches where collision probability exceeds a threshold. The US 18th Space Control Squadron screens approximately 20 million satellite pairs daily and issues thousands of conjunction warnings per week. Commercial operators like LeoLabs and ExoAnalytic provide independent tracking data. Starlink's autonomous avoidance system performs manoeuvres based on internal screening without human intervention.
The coordination problem
As LEO population grows from 8,000 active satellites today toward potentially 100,000+ by 2030, the current voluntary, notification-based system will become untenable. Key unresolved questions include: who has priority (first-come-first-served, or based on service value)? How are manoeuvre responsibilities assigned when two active satellites are on a collision course? Who pays for the consequences of a unilateral decision not to manoeuvre?