The Sky Is Not Empty Anymore
Picture a highway with no lanes, no traffic lights, no licensing authority, and no universally accepted rules of the road. Now imagine that highway is three-dimensional, wraps around the entire planet, and carries objects traveling at roughly 17,500 miles per hour. A fender-bender at that speed does not just disable two vehicles. It can shatter them into thousands of new projectiles, each one capable of triggering further collisions.
That is not a hypothetical scenario. It is an increasingly plausible description of low Earth orbit, the band of space roughly between 160 and 2,000 kilometers above the planet’s surface where the overwhelming majority of active satellites now operate. Over the past decade, the pace of launches has surged dramatically. SpaceX’s Starlink constellation alone had grown to more than 10,000 satellites in orbit by 2026. OneWeb, Amazon Leo (formerly Project Kuiper), and dozens of national and commercial programs have added or are adding hundreds more. Meanwhile, the catalog of tracked debris objects in orbit has grown to more than 25,000 pieces larger than 10 centimeters, according to estimates from the U.S. Space Surveillance Network, with researchers estimating that hundreds of millions of smaller fragments exist that cannot be reliably tracked.
The governance structures meant to manage this crowding have not kept pace. What exists today is a patchwork of national agencies, voluntary norms, bilateral agreements, and commercial services that often do not talk to each other, do not share data on the same terms, and carry no binding enforcement mechanism. Understanding why requires a tour through both the physics and the politics.
What Space Traffic Management Actually Means
Space traffic management, often shortened to STM, covers a range of activities: tracking objects in orbit, predicting potential conjunctions (the technical term for a close approach between two objects), issuing warnings to satellite operators, and coordinating maneuvers to avoid collisions. It also, in principle, encompasses longer-term concerns such as deorbiting defunct satellites, licensing new constellations, and setting standards for how operators behave.
In practice, the United States has been the backbone of global space situational awareness for decades. The U.S. Space Force’s 18th Space Defense Squadron maintains the authoritative catalog of tracked objects and provides conjunction data messages to satellite operators worldwide, largely free of charge, through a web portal called Space-Track. This is an extraordinary public service, but it comes with significant limitations. The sensors underpinning it were designed primarily for national security purposes, not commercial traffic management. They struggle to track objects smaller than roughly 10 centimeters in low Earth orbit reliably, and the conjunction data they produce carries uncertainties that can make warnings difficult to act on.
When an operator receives a conjunction warning, it typically includes a probability of collision. The challenge is that those probabilities depend heavily on how well the positions and velocities of both objects are known, and for debris objects, orbital knowledge degrades quickly. A conjunction assessed at a one-in-10,000 probability of collision might actually carry far higher risk if the debris object’s orbit is poorly characterized. Operators must decide whether to maneuver based on incomplete information, knowing that a maneuver itself costs propellant and can introduce new uncertainties.
Commercial space situational awareness providers, including companies such as LeoLabs and ExoAnalytic Solutions, have built ground-based radar and optical networks to supplement government data, and in some cases to track smaller objects that government sensors miss. Their data is often more precise for the objects they cover, but it is not universally accessible or standardized. The result is a market for space safety information in which some operators have excellent awareness and others, particularly smaller operators in developing countries, have very little.
The Kessler Syndrome Concern
No discussion of orbital congestion is complete without addressing the scenario that NASA scientist Donald Kessler described in a 1978 paper co-authored with Burton Cour-Palais. The Kessler syndrome refers to a cascade effect in which the density of objects in a given orbital band becomes high enough that collisions generate debris faster than the environment can clear it through atmospheric drag. Once that threshold is crossed, certain orbital altitudes could become effectively unusable for generations, because each new collision creates more fragments that cause more collisions.
Whether any orbital shell is already past that threshold is a matter of active scientific debate. Researchers at NASA and at the European Space Agency have published modeling work suggesting that the debris population in some altitude bands may already be self-sustaining even without any new launches, meaning that even if humanity stopped launching tomorrow, debris-on-debris collisions would gradually increase the overall fragment count over decades. Others argue that the timeline for truly dangerous cascade is long enough that active debris removal, if pursued seriously, could still prevent the worst outcomes.
What is not disputed is that two high-profile events have already demonstrated the cascading potential. In 2007, China’s intentional destruction of one of its own weather satellites during an anti-satellite weapons test added thousands of trackable debris fragments to orbit in a single event, significantly increasing the debris population at altitudes around 850 kilometers. In 2009, the accidental collision between an operational Iridium communications satellite and a defunct Russian Kosmos satellite produced another large debris cloud. Both events are still adding to the hazard environment that every operator in those regions must navigate today.
Why Coordination Keeps Breaking Down
The fundamental problem in space traffic management is jurisdictional. Outer space is governed at the international level primarily by the Outer Space Treaty of 1967, which establishes that space is the province of all humankind and cannot be claimed by any nation. It assigns responsibility for national space activities, including those of private companies, to the country that licenses or supervises them. But it provides no mechanism for resolving conflicts between operators from different countries, no binding traffic rules, and no enforcement authority.
The United Nations Committee on the Peaceful Uses of Outer Space serves as the primary international forum for space governance, but it operates by consensus, which means that disagreements among major spacefaring nations can block meaningful progress for years. Debris mitigation guidelines have been developed through that body, most notably a set of voluntary guidelines that recommend, among other things, that operators deorbit satellites in low Earth orbit within 25 years of the end of their missions. Compliance with even these modest voluntary guidelines has historically been inconsistent. Research tracking operational behavior has found that a substantial fraction of satellites reaching end of life have not met the 25-year deorbit guideline, though the numbers have varied depending on the study and the year examined.
In recent years, the U.S. Federal Communications Commission took a more assertive step by updating its rules to require that satellites in low Earth orbit licensed under U.S. jurisdiction deorbit within five years of mission end rather than 25. That was a notable tightening of domestic standards, but it applies only to satellites licensed by, or seeking market access in, the United States, and has no direct effect on satellites that never serve the U.S. market. The international race to offer favorable licensing conditions, sometimes called regulatory arbitrage, means that operators can seek out permissive jurisdictions, undercutting stricter national standards.
The challenge of coordination is also partly technical. There is no universally agreed standard for how operators should communicate collision avoidance intentions to each other. When two satellites from different operators are on a potential collision course, the question of who maneuvers is often resolved through informal outreach, sometimes via email, sometimes through third-party intermediaries, and sometimes not at all if an operator lacks the means to maneuver or the awareness that a conjunction is occurring. Active satellites can, in principle, move out of the way. Debris cannot.
The Commercial Boom and Its Complications
The rapid growth of large commercial constellations has introduced a new dynamic that governance frameworks were not designed for. A single operator running thousands of satellites, as SpaceX does with Starlink, generates a vastly disproportionate share of conjunction events simply by occupying so much of the available orbital volume. SpaceX has developed its own automated maneuvering system and shares data with the Space Force, and the company has argued that its approach to coordination is responsible. Critics, including some researchers and competing operators, have argued that the sheer volume of Starlink maneuvers places burdens on other operators and that the constellation’s scale creates systemic risks that individual operator diligence cannot fully address.
This tension points to a broader governance gap. There is no international body with the authority to cap constellation sizes, require operators to reserve orbital slots in advance in low Earth orbit the way the International Telecommunication Union allocates radio frequencies for geostationary satellites, or mandate specific data-sharing arrangements between commercial actors. The ITU does manage spectrum and orbital positions for geostationary orbit, but extending that kind of centralized coordination to low Earth orbit, where satellites move continuously relative to the Earth’s surface, raises complicated technical and political questions that have not been resolved.
Some researchers and policy analysts have argued for a more formal registry and insurance system analogous to maritime law, in which liability for collisions and debris creation would create economic incentives for careful behavior. Others have pointed to proposals for a dedicated international coordination body with real authority, rather than a voluntary forum. Neither approach has attracted sufficient political will to advance rapidly, partly because the nations with the most to gain from open access to orbit, including major spacefaring states, are reluctant to accept constraints on their own programs.
What Comes Next
The trajectory, absent significant policy change, points toward continued degradation of the orbital environment. The number of active satellites is expected to keep growing, debris accumulates faster than current deorbit rates can compensate for, and the verification and enforcement mechanisms that would make governance meaningful do not yet exist.
There are genuine reasons for cautious optimism, though they tend to be incremental. Active debris removal has moved from a purely theoretical concept to a field with actual mission demonstrations. Astroscale, a Japanese company, has conducted in-orbit demonstrations of proximity operations technologies aimed at removing debris. The European Space Agency has pursued a debris removal mission targeting a specific defunct ESA satellite. These missions are costly, technically complex, and each removes only a single object, but they represent proof that the problem can be addressed mechanically, not just managed around.
On the data side, there is genuine momentum toward more open and standardized sharing of space situational awareness information. Initiatives within the Space Force, among commercial providers, and in some multilateral forums have made more data more accessible than was the case a decade ago. The question is whether that momentum can be institutionalized before the debris environment reaches a threshold where individual operator diligence becomes insufficient.
The underlying challenge is one of collective action. Each individual operator, acting rationally in its own interest, has reasons to launch its satellites, minimize maneuvering that costs propellant and shortens satellite life, and defer expensive deorbit measures. The consequences of that aggregated behavior fall not on any single operator but on everyone who depends on space infrastructure, which in 2026 includes virtually every sector of the global economy. Navigation, weather forecasting, financial transactions, telecommunications, climate monitoring, and military operations all depend on satellites operating in the very environment that is slowly being cluttered.
The physics of the problem are unforgiving. A debris fragment the size of a marble, traveling at orbital velocity, carries enough kinetic energy to disable a spacecraft. The governance of the problem is, at present, unequal to the physics. Closing that gap will require not just better technology but a level of international cooperation that has so far proved elusive, and a willingness among the world’s most powerful spacefaring actors to accept constraints on their own ambitions for the sake of a shared resource that, once seriously degraded, cannot easily be restored.