As humanity’s reliance on space infrastructure grows, so does the responsibility to maintain a sustainable space environment. One of the most pressing challenges in modern space operations is the growing accumulation of space debris, which poses a significant risk to both current and future space missions. Efforts to mitigate this issue have been undertaken by governments, international organizations, and the private sector. These efforts have culminated in a variety of mechanisms aimed at addressing the risks posed by space debris and promoting space safety and sustainability.
The European Space Policy Institute (ESPI), in collaboration with the European Space Agency (ESA), published the ESPI Report 93: “A Party for Everyone? Analysing International Efforts in Space Debris Mitigation”. This report maps out the international landscape of space debris mitigation, providing a detailed comparative analysis of various international mechanisms. You can access the full report here.
Based on the ESPI report, and other sources, this article provides an overview of international activities in mitigating space debris.
Overview of Space Debris
Space debris, also known as orbital debris or space junk, consists of defunct satellites, spent rocket stages, and fragments resulting from collisions or explosions. The proliferation of this debris increases the likelihood of catastrophic collisions, which could further compound the problem. As a result, mitigating the creation of new debris and managing existing debris has become a focal point for international space actors.
Key International Instruments for Space Debris Mitigation
The ESPI report outlines 15 key international instruments that have been introduced to address space debris mitigation. These instruments represent efforts from various stakeholders, including governments, space agencies, industries, and non-governmental organizations (NGOs). Below is a summary of each of these mechanisms and their contributions to space debris mitigation efforts.
1. IADC Space Debris Mitigation Guidelines
- Released: 2002, updated in 2021
- Main Actors: Governments, Agencies, Industry, Academia, NGOs
- Developed by the Inter-Agency Space Debris Coordination Committee (IADC), these guidelines form the foundation for many national and international space debris mitigation policies. They provide comprehensive instructions to prevent the creation of new debris by addressing on-orbit explosions, collisions, and the disposal of satellites post-mission. Updated in 2021, the guidelines now include recommendations for geostationary orbit (GEO) disposal, break-up causes, and re-entry risks.
2. European Code of Conduct for Space Debris Mitigation
- Released: 2004
- Main Actors: Governments, Agencies, Industry, Academia, NGOs
- This voluntary code was developed by the ESA and four European national space agencies to promote responsible space operations. It provides flexibility for different space missions while maintaining a focus on debris prevention. The code, updated annually, encourages coordination among agencies and aligns with international standards to ensure sustainable space activities.
3. UN COPUOS Space Debris Mitigation Guidelines
- Endorsed by the UN General Assembly in 2007
- Main Actors: Governments, Agencies, Industry, Academia, NGOs
- The United Nations Committee on the Peaceful Uses of Outer Space (COPUOS) developed these guidelines based on the IADC guidelines, expanding their scope to include international treaties and principles on outer space. These guidelines aim to limit debris released during normal operations and minimize risks of break-ups and collisions. They also discourage intentional destruction of space assets, reinforcing peaceful space activities.
4. Recommendation ITU-R S.1003-2: Environmental Protection of the Geostationary-Satellite Orbit
- Published: 2010
- Main Actors: Governments, Agencies, Industry, Academia, NGOs
- Developed by the International Telecommunication Union (ITU), this recommendation focuses on minimizing debris in geostationary orbits. It includes guidelines for removing satellites from GSO at the end of their mission to prevent overcrowding. Although non-binding, the recommendation is widely respected and followed by satellite operators worldwide.
5. ISO 24113: Space Systems – Space Debris Mitigation Requirements
- Originally published: 2010, updated in 2023
- Main Actors: Governments, Agencies, Industry, Academia, NGOs
- This ISO standard provides detailed technical requirements for space debris mitigation, covering satellite design, protected regions, and mission planning. The standard applies to all spacecraft, regardless of size, and is designed to ensure that operators adhere to best practices in collision avoidance, post-mission disposal, and space traffic coordination.
6. UN COPUOS Guidelines for the Long-Term Sustainability of Outer Space Activities
- Adopted: 2019
- Main Actors: Governments, Agencies, Industry, Academia, NGOs
- These guidelines were developed by the UN COPUOS Long-Term Sustainability Working Group over a decade. They provide voluntary measures to ensure the safe and sustainable use of outer space for both governmental and non-governmental entities. The guidelines cover a broad scope of activities, including space weather, spectrum management, and scientific R&D, beyond traditional debris mitigation measures.
7. SIA Principles of Space Safety for the Commercial Satellite Industry
- Released: 2019
- Main Actors: Governments, Agencies, Industry, Academia, NGOs
- Developed by the U.S.-based Satellite Industry Association (SIA), these principles focus on responsible space operations for the commercial satellite sector. They emphasize transparency, space situational awareness (SSA), and collision avoidance. The principles also call for 24/7 availability of Points of Contact (PoCs) to address space safety hazards.
8. Space Safety Coalition’s Best Practices for the Sustainability of Space Operations
- First Released: 2019, updated in 2023
- Main Actors: Governments, Agencies, Industry, Academia, NGOs
- The Space Safety Coalition (SSC) is an ad-hoc group of private space companies that develops best practices for space operations. These voluntary guidelines apply to all spacecraft and provide a comprehensive set of practices for collision avoidance, post-mission disposal, and space sustainability.
9. CONFERS Recommended Design and Operational Practices
- Issued: 2019, last revised in 2022
- Main Actors: Governments, Agencies, Industry, Academia, NGOs
- The Consortium for Execution of Rendezvous and Servicing Operations (CONFERS) provides industry-led guidelines for satellite servicing, including maintenance, repair, and on-orbit assembly. These guidelines focus on the safe and sustainable execution of rendezvous and proximity operations (RPO) and on-orbit servicing (OOS), ensuring that satellite servicing activities do not contribute to space debris.
10. Paris Peace Forum’s Net Zero Space Initiative
- Released: 2021
- Main Actors: Governments, Agencies, Industry, Academia, NGOs
- The Net Zero Space Initiative, announced at the 4th Paris Peace Forum, aims to achieve the sustainable use of outer space by 2030. The initiative calls for the avoidance of new hazardous debris creation and the remediation of existing debris. This voluntary initiative emphasizes international collaboration to ensure a sustainable future for space activities.
11. G7 Science and Technology Ministers’ Communiqué
- Released: 2023
- Main Actors: Governments, Agencies, Industry, Academia, NGOs
- This communiqué, issued during the G7 meetings in Japan, reaffirmed the commitment of G7 countries to the COPUOS and IADC space debris mitigation guidelines. The ministers emphasized the importance of space situational awareness and sharing best practices for mitigating space debris, particularly concerning anti-satellite (ASAT) testing.
12. World Economic Forum (WEF) Space Industry Debris Mitigation Recommendations
- Released: 2023
- Main Actors: Governments, Agencies, Industry, Academia, NGOs
- Developed by the World Economic Forum (WEF), these recommendations outline specific criteria for space debris mitigation, including a 90-95% success rate for post-mission disposal and the active management of orbits for satellites above 375 km. The recommendations emphasize collaboration between private and public sectors to improve space sustainability by 2030.
13. ESA Space Debris Mitigation Requirements
- Released: 2023
- Main Actors: Governments, Agencies, Industry, Academia, NGOs
- As part of ESA’s Zero Debris approach, these updated requirements mandate the reduction of the post-mission disposal phase for low-Earth orbit (LEO) satellites and introduce collision avoidance standards. The requirements reflect ESA’s commitment to reducing space debris and promoting space sustainability through stringent regulations.
14. Global Satellite Operators’ Association (GSOA) Code of Conduct on Space Sustainability
- Released: 2023
- Main Actors: Governments, Agencies, Industry, Academia, NGOs
- The GSOA Code of Conduct focuses on promoting responsible behavior in space activities, particularly for satellite operators. It emphasizes the importance of limiting in-orbit collisions, preserving human life, and mitigating the impacts of space activities on optical astronomy. The code promotes collaboration among satellite operators to ensure the sustainable use of space.
15. Zero Debris Charter
- Announced: 2023
- Main Actors: Governments, Agencies, Industry, Academia, NGOs
- The Zero Debris Charter, initiated by ESA, promotes a global commitment to achieving debris neutrality by 2030. The charter unites a diverse group of space actors, including governments, industries, and academia, in a collective effort to minimize debris creation and ensure sustainable space operations.
Comparative Evaluation of International Mechanisms
The ESPI report provides a comparative analysis of these 15 instruments based on several criteria, including their purpose, structure, and representation. The analysis reveals that while there is a global consensus on the need for space debris mitigation, the implementation and enforcement of these mechanisms remain varied.
Key Insights from the Comparative Evaluation:
- Diverse Frameworks: The proliferation of mechanisms has led to a complex and fragmented landscape, where different actors operate within parallel frameworks. Some mechanisms are highly technical, focusing on specific numerical requirements, while others are broader, setting voluntary guidelines for best practices.
- Growing Stringency: Over the past few years, there has been a noticeable increase in the stringency of space debris mitigation measures. New instruments often introduce stricter requirements for satellite design, collision avoidance, and post-mission disposal.
- Private Sector Engagement: There has been a sharp rise in non-state-led initiatives, particularly from the private sector. Industry actors are playing an increasingly important role in driving the development of innovative solutions for space debris mitigation.
Summary
Space debris presents a growing challenge for the sustainability of space operations. The international community has responded with a range of instruments aimed at mitigating the risks posed by space debris. The ESPI Report 93 provides a comprehensive analysis of these efforts, highlighting both the progress made and the challenges that remain. As the space sector continues to evolve, it is essential that international actors work together to ensure a safe and sustainable space environment for future generations.
