This piece has been published as a complementary extension to a previous paper published by Carleton University’s Jean Monnet Network on EU-Canada Relations in partnership with the University of Antwerp. Read that piece here.
PART I: Understanding the Space Debris Problem in LEO
Terrestrial activity increasingly depends upon the structural and functional integrity of the satellites currently threatened by debris in low-Earth orbit (LEO). From everyday civilian applications, including telecommunications, weather forecasts, and online banking, to military applications including intelligence, imaging, and surveillance and reconnaissance (ISR), to developmental applications including the provision of Internet to remote geographic locations, LEO is a vital domain for the provision of services upon which we all depend. As res communis territory, outer space is no stranger to the tragedy of the commons market failure. As the LEO economy continues to grow, the proliferation of new actors, smaller and cheaper satellites, and decreasing launch costs all conspire to undermine the provision of the global public good that is a sustainable debris-free orbit.
The LEO economy, as defined by the National Aeronautics and Space Administration (NASA), is the “production, distribution, and trade of goods and services in low-Earth orbit,” which has grown exponentially over recent decades to include more stakeholders on both the supply and demand sides (NASA last modified 2022). The LEO economy falls within the broader emerging space market, which is forecasted to be worth up to $3 trillion USD in the coming decades with the number of commercial spacecraft in LEO projected to be in excess of 100,000 by 2030 (Hollinger and Learner 2022, 17). While the burgeoning LEO economy has supported the development of many of the aforementioned technologies that humankind depends upon, increased launches and collisions between existing pieces of debris guarantee that the amount of debris in LEO will increase in the coming years. Indeed, the realization of the Kessler Syndrome is quickly becoming a reality in LEO, whereby the density of existing debris is high enough to facilitate a chain-reaction of collisions that destabilize the environment and enable the instant destruction or deactivation of space-based assets (ESA 2020). The effects of the Kessler Syndrome are arguably already being felt following three major debris-generating events. In 2007, China launched an interceptor missile to destroy one of its defunct weather satellites, generating over 150,000 pieces of trackable debris (Pelton 2015, 3). In 2009, the US Iridium 33 communications satellite collided with the defunct Russian weather satellite, Kosmos 2251, which generated over 2,100 pieces of trackable debris (Hildreth and Arnold 2014, 3). And finally, in 2021 when Russia launched a direct-ascent ASAT missile against one of its own inoperative satellites, Kosmos 1408, which generated over 1,500 pieces of trackable debris (Blinken 2021). Importantly, the 2021 event forced the ISS to maneuver out of the way of the debris, which threatened its operations and the lives of its crew (Wattles and Hunt 2022).
Similar to the provision of other global public goods, confronting the debris problem in LEO through policies of mitigation and remediation presents many nuanced legal, policy, and logistical challenges. In space, these challenges are exacerbated by the fact that outer space is not under the jurisdiction of any one state, not subject to any tax-collecting authorities, and not beholden to any singular global authority that can impose sanctions or enforce action (Pelton 2015, 33). Undoubtedly, our continued use of LEO will depend upon our collective stewardship of this fragile environment. This policy paper will add to previous work on the debris problem in LEO published by Carleton University’s Jean Monnet Network on EU-Canada Relations by highlighting key legal and technical considerations with regards to orbital debris pursuant to the outer space treaty regime, the positions of two emerging and maturing space-faring powers, India and Japan, and the rise of the private sector in the orbital debris problem. This piece concludes with two policy recommendations for the space community writ large.
PART II: Key Legal & Technical Considerations
Increasing contemporary launches combined with historic “fire and forget” launches have created insurmountable congestion within LEO (Mey 2012, 252). As such, active debris removal (ADR) alongside other remedial options, such as de-orbiting to a graveyard orbit, have been touted as the only viable options to ensure a sustainable LEO environment. Such ADR, however, is plagued by many technical and legal barriers. In the first place, there is no global consensus on the definition of what space debris is and is not. This lack of a legal definition makes it difficult for state and non-state actors to identify which objects in LEO would be available for removal and to apply the outer space legal regime in good faith to the space debris problem. Neither the 1967 Outer Space Treaty (OST) nor any of the other subsequent treaties in the canon of UN space law make mention of the term “space debris” but rather use the term “space object”. For example, Article I of the 1972 Liability Convention defines space object as “including the component parts of a space object as well as its launch vehicle and parts thereof” (Liability Convention 1972, Article I). While it may be convenient to equate “space debris” with “space objects” in an attempt to simplify the application of international space law to the debris problem, ambiguity remains as to whether space debris can amount to “component parts” and thus adhere to the definition of “space object”.
A second key consideration lies with the ownership of the space object in question. Pursuant to Article VIII of the OST, launch states retain exclusive jurisdiction and control over the space objects launched from their territory while the object remains in space, on a celestial body, or upon its return to Earth (Outer Space Treaty 1967, Article VIII). Given such exclusive jurisdiction, it follows that no other state can interfere with the space object without prior consent from the launch state. Further, if “space debris” is understood as a “component part” of a space object, then any fragment or component of a space object, no matter how small, can be considered a discrete space object in its own right, and subject to the jurisdiction and control of the launch state (Listner 2021).
Following questions with regard to jurisdiction and control, the third key consideration stems from questions of liability and attribution, particularly in the event of an unintended collision or damage during the debris removal process. While the Liability Convention provides that the launch state remains liable for damages should its space object cause damage on Earth or to aircraft flight (Liability Convention, 1972, Article I), the treaty makes no express provisions for damage caused by debris removal activities. Further, such liability can only be determined if attribution on both sides is possible, namely, the state to whom the debris belongs and the state that is undertaking the debris removal. Given the size and the state of debris, it can be difficult to discern to whom the debris belongs and to whom the fault standard should apply.
Finally, in regards to ADR, states and private actors may be unwilling to cooperate in such activities owing to the need to share technical and potentially proprietary information that may be necessary for the success of the ADR mission (Hildreth and Arnold 2014, 12). Certain removal technologies may pose concern as well with regards to the weaponization of space given their potential dual-use nature. For example, the same net or harpoon used to remove debris from LEO may also be used to destroy or disarm an active satellite or spacecraft if used by bad faith actors.
PART III: Positions of Key Space-Faring States
In response to the growing debris problem, many historic space-faring states have developed their own definitions of space debris and have provided for this problem within their own national space policies and initiatives. The United States, through its Outer Space Policy Directive-3 and its National Space Policy, upholds the safety, stability, and operational sustainability of its space activities in order to minimize the debris environment (U.S. Government 2018; U.S. Government 2020, 14-15). The United States also maintains an active role within various space fora, including the United Nations Committee on the Peaceful Uses of Outer Space (UN COPUOS).
China, through its 2021 white paper, “China’s Space Program: A 2021 Perspective,” outlines many of its priorities with regards to space debris. These include developing technology to clean-up debris, becoming a leader in space environment governance, and expanding such governance by improving its debris monitoring systems, cataloguing database, early warning services, in-orbit maintenance, and debris mitigation (China National Space Administration 2022). In addition to supporting UN COPUOS and the Inter-Agency Space Debris Coordination Committee (IADC), China also maintains its multilateral participation through exchanges on space debris and long-term sustainability of outer space through mechanisms such as the Space Debris Work Group of the China-Russia Space Cooperation Sub-Committee and the Sino-US Expert Workshop on Space Debris and Space Flight Safety (China National Space Administration 2022).
Domestic Russian law, pursuant to Section I Article IV of its Law of Space, provides that the harmful pollution of space leading to unfavorable environmental changes is prohibited (Russian Federation 1993). Following this, Russia has codified many national space laws that expressly provide for the treatment and mitigation of space debris; however, recent actions in 2009 and 2021 call into question the sanctity of such legislation.
By contrast, the EU maintains a robust and heavily enforced space policy. A key pillar of its policy on space debris is enshrined within the 2004 European Code of Conduct for Space Debris Mitigation. The code has the primary objectives of preventing on-orbit break-ups and collisions, the removal and subsequent disposal of spacecraft and orbital stages upon end-of-mission, and the limitation of objects released during normal operations (UNOOSA 2004). In addition to this policy, the EU has also commissioned the active mitigation and remediation of space debris through its 2019 REDSHIFT Project (European Commission 2019) and its upcoming 2025 debris removal mission in partnership with the Swiss start-up, ClearSpace (Clery 2020).
Recognizing the threat space debris poses, Canada maintains three national mechanisms related to such debris: the 2007 Canadian Remote Sensing Space Systems Regulations, the Canadian Space Agency’s adoption of the IADC’s Space Debris Mitigation Guidelines in 2012, and the 2014 Canadian Client Procedures Circular for Licensing of Space Stations (UNOOSA Canada 2022).
While these entrenched space-faring states have the technical expertise and resources to dedicate to the development of their own national mechanisms to confront the space debris problem, it is interesting to note the progress made by two emerging and maturing space powers, notably India and Japan.
India
As a maturing space actor, India has maintained the position that it seeks to use space and space technology for peaceful purposes. However, at the time of writing, it does not maintain an official space policy defining its goals—with regards to debris or otherwise—in outer space (Rohera 2022). At a recent presentation to the United Nations Office for Outer Space Affairs (UNOOSA), Indian representatives highlighted the state’s commitment to tackling the space debris problem by engaging with partners within international cooperation and through bilateral cooperation with leading space actors. On the former, India highlighted its commitment to the IADC by maintaining representation in all working groups and by participating in IADC’s re-entry prediction campaign.
India also participates in space debris-related deliberations in the International Organisation for Standardization (ISO) Working Group 7, which specializes in space debris, as well as in the International Academy of Astronautics Working Group on Space Debris and Space Traffic Management. Bilaterally, the Indian Space Research Organization (ISRO) participates in space debris training workshops hosted by the European Space Agency (ESA) and in space situational awareness workshops with the Centre national d'études spatiales (CNES) (Anilkumar 2022). Most recently, the ISRO has partnered with NASA to establish dedicated observational facilities through the joint NASA-ISRO synthetic aperture radar mission (NASA 2020). Importantly, however, in March 2019 India conducted its first ASAT test that struck and destroyed one of its own Indian Microsat-R satellites. Given the relatively low altitude at which the test was launched, most of the debris generated should have already decayed, or be in the process of decaying, unlike similar tests conducted by Russia and China in previous years (Tellis 2019).
Japan
Guided by its 2018 Space Activities Act, Japan continues to be a responsible space actor within the realm of space debris mitigation. The Act allows the Government of Japan to license non-governmental entities’ activities to launch and control spacecraft within Japanese jurisdiction, and all activities are required to satisfy specific criteria, such as prevention of on-orbit breakup and post-mission disposal, so as to prevent the generation of space debris. The Japan Aerospace Exploration Agency (JAXA) also maintains its own space debris mitigation standard, which provides in-depth technical procedures for debris mitigation areas, including re-entry risks. In November 2021, Japan developed national guidelines for on-orbit servicing to facilitate end-of-life service and active debris removal by collaborating with the private sector. In partnership with the private sector, Japan is investigating ways to best remove large pieces of debris in crowded orbital bands, and has been developing technology to measure, monitor, and gather information on the characterization and accumulation of space debris. JAXA’s Risk Avoidance Support Tool Based on Debris Approach Collision Probability (RABBIT) is a good example of this (UN COPUOS 2022). Recently, Japan and the United States ratified the Framework Agreement for Cooperation in the Exploration and Use of Outer Space, Including the Moon and Other Celestial Bodies, for Peaceful Purposes, which includes a significant focus on civil space cooperation that may be used as a vehicle to augment research and development efforts in space debris mitigation technology (Malekos Smith 2023).
While entrenched space actors, particularly the United States, remain the core hubs of space activity, a number of new states are increasingly becoming involved in this domain. The addition of space agencies in the Philippines, Costa Rica, and Rwanda, combined with the new Latin American and Caribbean Space Agency (ALCE) joining the ESA, and the Asia-Pacific Space Cooperation Organization (APSCO) mean that every region of the world now has a stake in space (Brukardt et al. 2022).
Despite times of conflict on Earth, the space domain has historically served as an area for collaboration amongst states. Given the high transaction costs and barriers to entry, it behooved states to opt for increased collaboration and cooperation. Such cooperation paved the way for the 1998 Intergovernmental Agreement that underpins the International Space Station and has similarly allowed for the negotiation and ratification of the Artemis Accords by 24 member states. However, in recent years such cooperation has become relegated to distinct blocs of states created along traditional terrestrial fault lines. The ESA and its member states were one of the first of such blocs, and in recent years similar blocs including the African Space Agency, the ALCE, and the Arab Space Coordination Group have emerged. Such blocs allow states to work closely with one another within the bloc but also allow for increased competition between blocs. Most recently, the Artemis Accords and the Sino-Russian Lunar Agreement serve as an example of such competition between blocs (Ben-Itzhak 2022).
Space debris, however, poses a common problem outside of the scope of great power competition that ought to be confronted by all major space powers collectively. In this sense, the world’s major space powers, particularly the United States, China, Russia, Canada, the EU, Japan, Russia, and India bear a unique responsibility in partnership with the private sector to combine resources, personnel, and expertise to address this problem (Manning 2023). While this seems like a stretch politically given the current geopolitical climate, the rules deficit that characterizes the space domain underpins the necessity for such cooperation.
Space debris orbiting Earth. Image source: WikiImages, licensed under CC0.
PART IV: Positions of Key Commercial Stakeholders & Private Sector Developments
When discussing the problem posed by increasing debris in LEO and potential remedial strategies, it is important to consider the landscape of those most affected by such debris. Within this category, there are five key stakeholders of note. First are launch providers, whose business models depend upon their ability to launch payloads into orbit. However, while they stand to become victims of an increasingly congested LEO, they are also a key part of the problem. Second are satellite operators, which—much like launch providers—are vital components to the LEO economy and are simultaneously responsible for the increased debris and some of the most affected victims of this debris. Indeed, mitigating and remediating debris is in the direct interest of satellite operators, and many are already starting to incorporate maneuverability and de-orbiting technologies onto their satellites. Third, and perhaps most interesting, are insurance companies, which may play an increasingly large role in the LEO economy as the risk of collision grows. Fourth are end-users of space-based assets who rely on such assets for military, commercial, and civilian applications. Finally, an emerging key stakeholder is the private sector and the many start-up firms that are working to commercialize the removal of space debris (Hatch et al. 2020).
Where state-based collective action to tackle the problem of debris in LEO has faltered, owing to the lack of binding, enforceable obligations and complex legal and technological challenges, the private sector appears to have picked up the proverbial gauntlet. Private firms across many of the aforementioned space-faring nations have made significant inroads into developing and testing technologies to be used for debris removal. Firms such as Rogue Space Systems Corporation in the United States, NorthStar Earth & Space in Canada, ClearSpace in Europe, and Astroscale in Japan are but a few of the private sector enterprises pioneering ADR technologies. The current legal framework for space does not directly address space debris, thus leaving the door open for private firms to both ideate solutions to overcome the technical problems of debris removal and play a role in crafting the policy that supports their involvement. Such a commercial frontier seems to have the support of government as seen in a 2021 statement where G7 members expressed their willingness to resolve many of the technical aspects of the debris problem with private firms (UK Space Agency, 2021). This has been supported by various private sector initiatives, including Apple co-founder Steve Wozniak signaling his plans to address the problem through his new company, Privateer Space, Astroscale’s successful 2021 launch of its End-of-Life Services by Astroscale demonstration (ELSA-d) mission, and Astroscale’s stated willingness to work with both governments and international organizations to craft policy vis-à-vis private efforts (Giordano, 2021).
Given the lack of state-driven public policy on space debris, such public-private partnerships may prove to be the way forward in tackling this problem. The increasing involvement of the private sector may spur further private investment in technology for space debris removal. Such partnerships have already begun with Astroscale, which has thus far partnered with Japan and the EU, and others including ClearSpace, OneWeb, and D-Orbit (Giordano 2021). Given the lack of bureaucratic inertia, the private sector may be better suited than governments to develop and implement the technology needed to remove debris, while acknowledging the long-term importance of keeping LEO free from debris and the potentially lucrative endeavor this may present. However, this will likely need to be done in conjunction with government-led regulation.
On the other hand, it is important to note that while the private sector may be best poised to tackle the problem of debris in LEO, they are also the ones largely responsible for its congestion. Such a conceptualization may render the need for bolstering international treaties and giving legal teeth to the UN and UN-sponsored guidelines. While this course of action should undoubtedly be considered, it is important to note that this scenario differs from a traditional tragedy of the commons. Unlike the traditional iteration in which the commons is diminished by firms’ activities, in this scenario the private sector is actively working to expand the commons. In this scenario, governments themselves stand to benefit from these initiatives (Giordano 2021).
PART V: Conclusion & Policy Recommendations
As state and non-state actors move to occupy space and celestial bodies on a more consistent and permanent basis, it behooves space-faring nations to forge and maintain cooperative partnerships with fellow states and private actors in the space domain. Understanding this, the following is a list of two potential policy recommendations that any space-faring states’ leadership may consider in concert with its public and private allies.
1. Harmonize the global position on and definition of space debris
While some states have formalized their positions on the topic of space debris and have actively made inroads to tackle this problem both operationally and through legislation, a globally agreed-upon definition of “space debris” does not yet exist. The semantic importance of such a definition cannot be understated, as such a definition would provide a focal point around which state and non-state space actors could gather and coordinate future policy and governance initiatives with respect to debris in LEO and beyond. Such a definition would need to be legally binding for any concrete effect and as such may be added as an addendum to the OST or ratified as a separate legal mechanism. Alternatively, using the existing canon of space law, states parties to the OST may engage in contextual treaty interpretation so as to reconcile the use of non-consensual ADR. Pursuant to Article IX of the OST, states parties are obligated to act in “due regard” and be “guided by the principle of cooperation and mutual assistance” with other states parties to the OST in the conduct of their space activities. Article IX also underpins states’ obligation to refrain from “harmful contamination” of the space environment (OST 1967, Article IX). A flexible and contemporary interpretation of the treaty and its provisions may be the key to resolving some of the legal challenges associated with debris removal.
2. Increase participation in multilateral fora vis-à-vis polycentric governance
International organizations, including UN COPUOS, provide the ideal forum for both space- and non-space-faring states to engage in coalition-building and network diplomacy to strengthen the current legal regime, including the canon of UN space law and the IADC Space Debris Mitigation Guidelines. In her seminal work, Elinor Ostrom advocates for systems of polycentric governance, which refers to a network of independent nodes that can make decisions both individually but can also coordinate amongst themselves to produce a joint output (Ostrom 2010, 552). As such, the interplay of these nodes allows polycentric governance to bring together a diverse range of stakeholders, which can improve issue linkages, cooperation, information sharing, and collective decision-making.
Given the legal nuance and technical complexity surrounding the problem of space debris, it behooves states to engage with a wide range of actors—both state and non-state—across a broad spectrum of expertise in order to develop solutions for the short-, medium-, and long-term. When functioning efficiently, a polycentric system of governance offers several advantages over traditional monocentric, or hierarchal, forms of governance, including improved access to distributed knowledge amongst actors, enhancing capabilities for learning and innovation, increased capability of mobilizing a wider range of stakeholders, underscoring the system’s legitimacy, enhanced response to changing circumstances and advancements, which is an important quality within the space domain as our understanding of the environment and of the debris problem changes, improved ability to connect actors and processes from the local to global level, and increased political feasibility within a supranational context in which states can be wary of new international agreements and organizations (Lambach and Wesel, 2021, 4).
By engaging productively with other state and non-state actors within existing international organizations, like UN COPUOS, and through a framework of polycentric governance, states may strengthen the current space legal regime to better address the space debris problem. For example, the 1976 Registration Convention seems primed for an update, pursuant to Article IV(2), which permits launch states to provide additional details on registered objects in orbit. Modification to Article IV(2) could be made such that launch states could indicate objects ready for salvage or removal, as they become available, thus consenting to other states or commercial actors de-orbiting the object and either returning it to the launch state or propelling it into a graveyard orbit. Such treaty modification is provided for pursuant to Articles IX and X of the treaty (Registration Treaty 1976, Articles IX and X).
Conclusion
The integrity and sustainability of LEO and successive orbital bands will depend upon our collective stewardship of this increasingly fragile environment. Given the direct benefits provided by a functional orbit to all, both on Earth and in the cosmos, it is in the direct interest of all space actors, both public and private, to work toward advancing a robust policy framework that responsibly addresses the problem posed by space debris. Given the highly technical and legally nuanced challenges posed by this problem, it behooves states to cooperate on both the state-to-state and private-public axis. Doing so would allow states to broaden their networks so as to advance their interests in maintaining a sustainable orbit, build strategic links with the private sector, disseminate information and take advantage of the innovation and technical expertise of the private sector, and ultimately exercise power within the network and beyond. Like any collective action problem, confronting the problem of space debris in LEO requires both cooperation and coordination. While the provision of public goods has traditionally fallen to governments, the shortcomings of current space law combined with the rise of the LEO economy suggest that there may indeed be free market solutions available for states willing to cooperate within this new commercial frontier.
*This article was edited by Michelle Zhang (Princeton University), Allison Blauvelt (Princeton University), and Emili Sabanovic (Georgia Institute of Technology).
Alexandra Chronopoulos is a recent graduate of the Norman Paterson School of International Affairs (NPSIA) at Carleton University where she specialized in the study of international organizations and global public policy. Her research interests lie in outer space policy and governance, particularly issues related to space debris, inter-state cooperation in space, and the intersections of international law and the private sector within the space domain. She previously held a position as a Strategic Analyst at the Department of National Defence in Ottawa and is currently preparing to start a new role at the European Space Policy Institute in Vienna. She can be found on LinkedIn at: https://www.linkedin.com/in/alexandrachronopoulos
Acknowledgements
Alexandra would like to thank her JPIA editing team, Michelle Zhang, Emili Sabanovic, and Allison Blauvelt, for all of their work on getting this piece to publication. She is also grateful to the Jean Monnet Network on EU-Canada Relations for providing the research grant that allowed her to write the initial paper upon which this piece is based. Alexandra would also like to thank Professor Christopher Penny of NPSIA for his constant encouragement and inspiring words, and her partner for his tireless proof-reading and support.
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