Right now, around 30,000 objects larger than a softball are being tracked in Earth orbit. By 2030, that number is expected to climb past 100,000. Add the Moon to the picture and the problem compounds: commercial lunar missions, government orbiters, crewed landers, and eventually permanent surface infrastructure will all share a region of space that has no traffic authority, no air traffic control equivalent, and no universally agreed rules for who yields to whom. That gap has a name: space traffic management , or STM. It covers everything from collision avoidance between satellites to coordination of lunar approach corridors, orbital slot assignments around the Moon, and the deconfliction of hundreds of spacecraft operating simultaneously in cislunar space. Getting STM right is not just a safety exercise. It is a prerequisite for the entire commercial lunar economy. AI-generated image Thousands of tracked objects already populate Earth orbit. The cislunar extension of this problem is arriving faster than the governance framework. Credit: AI-generated illustration What Space Traffic Management Actually Covers The International Academy of Astronautics defines STM as "the set of technical and regulatory provisions for promoting safe access into outer space, operations in outer space, and return from outer space to Earth free from physical or radio-frequency interference." That definition is deliberately broad, and it has to be. The problem spans multiple domains simultaneously. In low Earth orbit, the primary concern is collision avoidance: tracking debris, sharing orbital data between operators, and issuing maneuver advisories when two objects come within dangerous proximity. The U.S. Space Force runs the 18th Space Control Squadron, which maintains the Space Surveillance Network and currently tracks approximately 27,000 objects. Most conjunction warnings are handled through the Space-Track.org database, which operators consult voluntarily. Cislunar STM introduces complications that Earth-orbit systems were never designed to handle: • Vast distances: The Earth-Moon system spans roughly 384,000 kilometers on average. Spacecraft transit times are measured in days, not orbits. A conjunction warning issued too late has no useful value. • No established tracking infrastructure: Ground-based radar systems are optimized for objects in low to medium Earth orbit. Tracking objects near the Moon or in the L4/L5 Lagrange points requires new sensor networks or space-based assets. • Mixed operators: NASA, ESA, JAXA, ISRO, Roscosmos, CNSA, ispace, Astrobotic, Intuitive Machines, and dozens of emerging commercial players will all occupy cislunar space simultaneously within the decade. None of them are currently required to coordinate with each other. • Multiple orbital regimes: Cislunar space includes low lunar orbit (LLO), elliptical frozen orbits, near-rectilinear halo orbits (NRHO), and various Lagrange point halos. Traffic management rules that work in one regime may not apply in another. • Communication delays: Round-trip light travel time between Earth and Moon is about 2.6 seconds, limiting real-time collision avoidance in the same way it exists in LEO. Autonomous onboard responses become more important. 27,000+ Objects tracked in Earth orbit (U.S. Space Force) 100+ Lunar missions planned or in development (2024-2030) 2.6 sec Round-trip light delay Earth-Moon 0 Binding international cislunar STM rules today 5+ Nations with active lunar programs NRHO Gateway station orbit: Near-Rectilinear Halo Orbit The Existing Framework (and Where It Falls Short) Current international space law rests on a foundation built in the 1960s, when the United States and Soviet Union were the only players. The 1967 Outer Space Treaty established that space is the "province of all mankind" and prohibited nations from claiming sovereignty over celestial bodies. The 1972 Liability Convention established that launching states bear responsibility for damage caused by their space objects. The 1976 Registration Convention requires that space objects be registered with the United Nations. None of these treaties were written with traffic management in mind. The Outer Space Treaty says nothing about collision avoidance. The Registration Convention does not require operators to share orbital data in real time. There is no equivalent of the International Civil Aviation Organization (ICAO) for space, no body with actual authority to assign orbital corridors or mandate maneuvers. In 2018, U.S. Space Policy Directive-3 assigned responsibility for civil space traffic management to the Department of Commerce rather than the Department of Defense, with the intent of creating a more operator-friendly, transparent system. The Commerce Department's Office of Space Commerce has been building the Open Architecture Data Repository (OADR) as a public-facing catalog to complement the military's SSN data. But SPD-3 was a domestic policy document. It cannot bind non-U.S. operators. The Governance Gap The 1967 Outer Space Treaty prohibits national sovereignty over celestial bodies but says nothing about traffic rules near them. A spacecraft from one nation has no legal obligation to maneuver for another. In a cislunar environment with dozens of operators, that ambiguity creates real collision and interference risk. The United Nations Committee on the Peaceful Uses of Outer Space (COPUOS) has been working on long-term sustainability (LTS) guidelines since 2010. The 2019 LTS guidelines include recommendations around orbital debris mitigation, sharing of space situational awareness data, and communication protocols, but they are voluntary and non-binding. Nations adopt them at their own discretion. Cislunar-Specific Challenges: Orbits, Corridors, and the Lunar South Pole Problem Lunar orbital mechanics introduce some specific challenges that Earth-orbit STM has no analog for. The Moon has no significant atmosphere, so aerobraking is not available and all orbital decay must be managed actively. The lunar gravity field is also highly irregular due to mass concentrations ("mascons") buried beneath the surface, which perturb spacecraft orbits in ways that are hard to predict without detailed modeling. Low lunar orbit (roughly 100 km altitude) is particularly unstable. Most spacecraft in LLO will impact the lunar surface within weeks to months without regular orbit correction burns. This means every spacecraft in LLO is a potential piece of debris if its propulsion system fails. Unlike LEO, where atmospheric drag eventually pulls debris down and burns it up, lunar debris just stays where it is indefinitely. Near-rectilinear halo orbits (NRHO), like the one planned for the Lunar Gateway station, are much more stable. The Gateway will occupy a southern NRHO with a period of about 6.5 days, looping close to the lunar south pole (roughly 3,000 km) at periapsis and far away (roughly 70,000 km) at apoapsis. This orbit is stable enough to go unoccupied for extended periods, which is operationally useful. But it also means that spacecraft approaching the Moon for crew transfer or cargo delivery will need to rendezvous with a target moving in a complex three-dimensional path relative to both the Moon and Earth. AI-generated image Building a cislunar STM framework requires coordination between space agencies, commercial operators, and governments that may have competing geopolitical interests. Credit: AI-generated illustration The lunar south pole is where the STM problem gets most acute. Every major space agency and most commercial lander operators are targeting a crescent of terrain within a few hundred kilometers of the pole, drawn by the potential presence of water ice in permanently shadowed craters. When Artemis landers, ispace landers, ISRO's Chandrayaan missions, China's Chang'e program, and commercial CLPS deliveries are all targeting the same region within the same multi-year window, approach corridors, landing zones,