Op-ed | Parking spots for satellites reduce congestion, promote technological growth

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Just imagine: ninety-nine percent of the Earth-observation and communications satellites expected to launch by 2030 will be inserted into orbits without a comprehensive governance regime.

The rapid expansion of launch capability and increasing density of space vehicles is already testing the limits of existing structures intended to help manage space traffic and mitigate risk. The existing system is fragmented at best, and the tools for risk mitigation are limited, increasing the chances it will still fall short of preventing potential asset loss and associated litigation.

The time is now for governments, technologists, and investors to collaborate on how to define and allocate orbital slots and capacity – namely the positions above Earth occupied by satellites — as part of an improved approach to space traffic management (STM).

A new STM system will be critical to unlocking the growth potential of the new space economy. There are many components to STM – including space debris management (SDM) and space situational awareness (SSA) technology and requirements – which incentivize the creation of globally acceptable standards and governance.

Expanding orbital slot and capacity allocation to include orbits beyond GEO is another key component of effective STM. The concept of slot allocation is not new, as slots for geosynchronous orbit (GEO) have been managed by the International Telecommunication Union (ITU) since 1963.

However, no similar system or body for allocating slots currently exists for medium Earth orbit (MEO), highly elliptical orbit (HEO), or low Earth orbit (LEO,) which is where the vast majority of new satellites are placed in orbit.

Benefits of an orbital slot regime for LEO and MEO include improved protection for the complete space economy, also encompassing the full suite of space value chain applications. Sovereign and commercial satellite communications (SATCOM), Earth Observation (EO), and positioning, navigation, and timing (PNT) services will all benefit from increased security, and this increased resilience to the space sector.

Based on our analysis and on projections from space insurance firm AXA XL, the total value of assets in orbit by 2030 may be as high as $230 billion, up from $38 billion today. The corresponding risk of asset loss growth to $1.9 billion (from just $65 million today) poses a great threat to the value of the space economy and incentivizes the development of a robust system to help manage current and future slot allocation.

As Beckett Jackson, principal with AE Industrial Partners, notes, “while private industry and investors have the ability and capital to develop solutions to safely manage proliferated LEO, the absence of a broadly recognized set of standards and policies creates uncertainty about customer needs, adoption cycles, and ultimately limits potential investment.”


The scientific research on orbital capacity clearly indicates the resource is finite. When juxtaposed with the similarly limited resource of spectrum allocation, the need for more cohesive orbital resource management is clear.

Richard Linares of MIT is currently leading research on the empirical and analytic limits of constellation size for given minimum separation distances. He says using reasonable minimum separation distances, individual shells can fit hundreds to thousands of satellites.

According to Linares, “Current constellation design practices typically involve individual shells for each operator separated by altitude. Another important consideration for capacity is how closely shells can be stacked vertically. Satellites don’t move in perfectly circular orbits — their orbits are affected by Earth’s non-spherical gravity field and by forces like atmospheric drag and solar radiation pressure.”

The vertical stacking of orbital slots, combined with separation requirements within those slots, could suggest two scientific parameter requirements as part of an STM regime to protect the economic activity within each shell. Slots and shells are used interchangeably in this article.

The importance of orbital slot allocation is matched by the importance of allocating orbital carrying capacity. Carrying capacity could define the safe constraints of ‘how much’ could be placed in given orbital regions, while so called slots would be a more detailed definition of the orbital parameters assigned to the particular satellites.

Limited structures currently exist for STM, and they remain fragmented by country, agency, and orbit. The ITU has played a critical role since it hosted the Extraordinary Administrative Radio Conference (also known as the Space Conference) in 1963, which focused on the allocation of radio frequencies for outer space activities. This was subsequently expanded to include the allocation of orbital slots for satellites in GEO, and despite challenges to this regime – including the attempt by seven equatorial countries to assert sovereignty over the slots above their borders with the 1976 Bogota Declaration – the ITU retains its role in allocating GEO slots, leaving the status quo unchanged.

The status quo has been maintained in part because the allocation regime has been reasonably effective in enabling and managing the growth of GEO as an orbit and avoiding over congestion, but structural limitations are apparent.

Orbital slots in GEO are a finite resource, and few remain available. Slots provide exclusive rights and are allocated on a first-come, first-served basis, and must be filled within five years of allocation, with the initial license lasting for 15 years, but can be held indefinitely if the operator replaces its satellites at the end of their lifespan. Due to scarcity and timeline for putting a satellite into service, obtaining an orbital slot in GEO poses a challenge for emerging space nations and newer commercial entrants.

Similarly, a useful existing spectrum and license management tool exists under current processes for licensing a LEO SATCOM constellation, but this only addresses the SATCOM segment of the space value chain. To gain access to proposed orbit and spectrum use, a company must file details about their proposal through a license application with the national regulator (the Federal Communications Commission/FCC in the U.S.), after which the filing moves to the ITU including details about orbital positions in addition to frequency coordination data.

However, the level of detail required in such a filing, which becomes public on the FCC website, is limited; the full scope of constellation size/scope/ maneuver capability/slot/capacity in company plans remains opaque. The inconsistencies within the U.S. FCC process are amplified when elevated to the international level; current processes fall far short of what’s needed.

There is growing recognition of the need to manage orbital congestion – the National Orbital Debris Mitigation Plan, released in July 2022 acknowledges the threat posed by the uncontrolled growth in debris – but this has not extended to establishing slot or capacity regimes for LEO, MEO or HEO.

A shortage of good slots and capacity within them already poses a problem in GEO, and this issue could arise in due course in other orbits. A 2020 report by the National Academy of Public Administration (NAPA), commissioned by the Department of Commerce as a study into the optimal structure to govern STM, concluded, “although space is vast, some commercially usable venues are limited. For example, current and expanding deployments of satellite constellations that provide broadband need to be positioned in low Earth orbit so that the latency — the time required for data to travel to the satellite and back — can be at speeds that are sufficiently fast for gaming, navigation, and other internet applications.

NAPA notes that “it may be more useful to think of some regions of orbital space as a common pool resource (CPR),” suggesting that to prevent a tragedy of the commons, robust governance structures are warranted to preserve access.


Spacefaring nations should come to consensus and create an international civil organization with a clear mandate to support STM efforts, including through the allocation of orbital slots and capacity for LEO and MEO. This is the most effective way to structure orbital slot and capacity definitions while preserving nation-states’ military space sovereignty. Such a body could be modeled on the International Civil Aviation Organization (ICAO), and effectively support governance by allocating slots while expanding SSA by tracking objects, thus improving overall STM capabilities.

The requirements of the space sector, and the pace at which it is growing, merit the establishment of a multinational body which can serve the diverse interests not just of various nations – both established space faring countries and emerging space economies – but also of innovative commercial solution providers, ensuring more equitable and sustainable long-term access to space.

ICAO traces its origins to the 1944 Chicago Convention, where 54 countries convened and established the core principles enabling international air transport. ICAO was officially established as a UN agency in 1947, with a mission to develop international policies and standards, conduct compliance audits, studies, and analyses, and help build aviation capacity. It is not a regulatory body and has no authority to close airspace or impose restrictions on airlines or airports, but instead coordinates and mediates among member states.

The structure of ICAO – with power drawn from the 193 member states, which fund and direct the organization – could inform the structure of a space-specific organization, which would draw power from governments of established space nations, while also ensuring that the interests of emerging space nations would be represented. It could help national space agencies and other entities with disparate interests better establish norms and coordinate responses to space-based events and incidents.

The argument for establishing an international organization to address slots in orbits beyond GEO is also not new – in 2002, the Federal Aviation Administration Office of Commercial Space Transportation (FAA-AST) proposed establishing an International Space Flight Organization (ISFO) to help manage international space traffic including launch and landing, and in 2011, a paper published in Studies in Space Policy called for the creation of an ICAO equivalent for space flight.

These suggestions pre-date the unprecedented growth of the space economy during the last decade, during which time the need for effective coordination has only become more acute.

In responding to the divergent interests of different nations in space, including allocating orbital slots in LEO and MEO, a new organization would benefit from being space-specific, with deep domain expertise and connections with the broader international space industry.

Establishing a stand-alone, space-specific entity would help focus organizational priorities, and reflect the broader trend in the space sector which is seeing a growing number of countries establish their own national space agencies and space components within the armed forces. This development would not need to infringe on or detract from the ITU or ICAO in their respective roles in supporting STM, rather it could complement their existing mandates.

Standards, service requirements, and interfaces should be harmonized, such that a known sovereign military framework can exist within the broader space traffic framework for governance. Space diplomacy – and the establishment of a foundational international civil space organization – has never been more urgent.

The value unlock of a governance structure will enable the growth of responsible SSA and STM companies, which protect space sustainability. Private sector firms including Neuraspace, Scout, Kayhan, and Privateer are already providing valuable contributions to ensuring the long-term viability of operations in congested orbits.

Companies operating in these fields will be key partners in providing critical capabilities such as collision avoidance, maneuverability, and de-orbit systems. These firms must also help lead by example in setting a standard for corporate responsibility in STM, which should include changing acquisition practices to only do business with firms which have de-orbiting plans and are supportive of a slot allocation regime.

Bruce Chesley, former Boeing chief architect responsible for technology investment and product development for space exploration, cybersecurity, missile defense and satellite systems for military and commercial applications, urges: “The safety of current constellations and the long-term sustainability of space services – especially in LEO – requires a more robust approach to orbital slot assignments.”

Given the complexity of designing and standing up a new entity designed to support orbital slot allocation, there is urgency to move quickly – before the lack of an existing regime for LEO and MEO begins to present real, rather than hypothetical problems. The process to establish an agency with parameters for global STM regime might involve the following steps:

  • Create an independent committee with the mandate from an international organization; the UN Committee on the Peaceful Uses of Outer Space (COPOUS) would be a leading candidate to organize such a committee
  • Establish the premise that said international committee will evolve within time to be the ISFO
  • Ensure that the committee’s first and immediate priority would be to calculate number of orbital slots available for, and orbital capacity available within each slot for, allocation in LEO, MEO, and HEO
  • Have the committee establish a baseline to calculate the level of acceptable risk of collision within each slot, based on a scientifically determined calculation for capacity within each slot
  • Have the committee present its recommended scientific methodology to determine the available LEO, MEO, and HEO orbital slots and capacity within each to the members of COPOUS
  • Have the committee establish a global requirement for commercial space launch to include a collision avoidance system in place which complies to specific safety standards to include a deorbit/decommission requirement
  • Have the committee establish global dispute resolution standards for spectrum, slot, and capacity for LEO, MEO, and HEO

The role of space in our global supply chain is growing rapidly, but the window of opportunity to protect equitable access to space may close too soon. The time to protect the current era of growth in space and on earth is now.

S. Sita Sonty is partner and associate director for aerospace and defense at Boston Consulting Group. Cameron Scott is BCG’s global sector manager. John Wenstrup is BCG senior partner and managing director, leading the firm’s West Coast technology group and global software practice.

This article originally appeared in the November 2022 issue of SpaceNews magazine.