“Best Practices for the Sustainability of Space Operations”

Version: 2.00

 April 2023

Since the first orbital launch in 1957, the number of artificial objects in Earth orbit has been growing. The corresponding increase in close approaches and collision risk to active space objects from collisions [ 1, 2 ] may lead to interruption of crucial space services [ 3 ].

Orbital debris population modeling indicates the potential for further increases in collision risk [ 4, 5, 6, 7, 8 ]; some of these studies indicate that even in the absence of new space traffic, orbital debris mitigation measures may be insufficient and debris removal remediation may be necessary. Accordingly, mitigation measures are needed to minimize orbital debris and preserve safe access to space in the future. Space industry stakeholders are aware of these challenges and have achieved key milestones to address them.

In 2002, the Inter-Agency Space Debris Coordination Committee (IADC) assembled a set of guidelines for international space debris mitigation [ 9 ], aimed at limiting the generation of debris in the environment in the short-term – through measures typically related to spacecraft design and operation – and the growth of the debris population over the longer-term, by limiting time spent in the low Earth orbit (LEO) region after the end of mission to 25 years. The IADC updated these Space Debris Mitigation Guidelines in 2007 as Revision 1 [ 10 ], 2020 (Revision 2) (no online presence found), and 2021 (Revision 3) [ 11 ]. The IADC also issued a statement on issues and concerns relevant to planned large LEO constellations [ 12 ].

The United Nations (UN) Committee on the Peaceful Uses of Outer Space (COPUOS), drawing largely upon the IADC’s initial set of orbital debris mitigation guidelines, developed its own reduced set of consensus Space Debris Mitigation Guidelines [ 13 ].

The UN General Assembly endorsed these guidelines in its resolution 62/217.

The International Organization for Standardization (ISO) develops international standards that address space debris mitigation. ISO’s top-level space debris mitigation standard is ISO-24113, “Space Systems — Space Debris Mitigation” [ 14 ]. This standard and its derivative standards to include [15, 16, 17, 18, 19 ], incorporate IADC and UN guidelines as well as commercial best practices and expected norms of behavior.

The Consultative Committee for Space Data Systems (CCSDS) is comprised of the major space agencies of the world and develops communications and data systems standards for spaceflight. CCSDS seeks to enhance governmental and commercial interoperability and cross-support while also reducing risk, development time, and project costs by developing, publishing and freely distributing international standards [ 20 ]. The CCSDS international standards for the exchange of orbit, attitude, conjunction, reentry, and event data are particularly relevant to exchanging space data to facilitate safety of flight.

Some spacefaring nations have set up a licensing scheme or national regulatory framework for the space operators in their country. In general, such national regulation reflects a combination of the UN, IADC, and/or ISO-24113, which generally refer to common mitigation measures [ 21 ].

Plans to increase our space population with more CubeSats and other small satellites, as well as new, large constellations of satellites, were not envisioned when the above- 3 mentioned guidelines and standards were established. These new planned spacecraft and constellations, coupled with improvements in space situational awareness, space operations, and spacecraft design, all provide an opportunity to expand upon established space operations and orbital debris mitigation guidelines and best practices.

In developing the following best practices, it was recognized that future efforts may be warranted to:

1) Adopt an existing forum or establish new forum(s) to create conditions favorable to the sharing of relevant space information and operator-to-operator coordination of space activities. Spacecraft operator communications and data sharing will remain the best strategy for avoiding collisions.

2) Address coordination between new large constellation satellite missions and operators existing in the targeted new mission orbit as early as possible to prevent unnecessary co-location or repeating conjunctions once on-orbit.

3) Collaborate with spacecraft manufacturers, governments, and intergovernmental agencies to deorbit all spacecraft after their operational life to achieve ultimate sustainability of the space environment. Create conditions for the development of deorbit servicers, international standards for servicer interfaces and operations, and servicer-friendly spacecraft designs, while not leaving a derelict spacecraft in an orbit that will not passively decay within 5 years, or which is not a seldom[1]used or designated graveyard orbit.

The undersigned space industry stakeholders hereby endorse and will promote and strive to implement within their respective organizations the best practices identified and described herein as a valuable advancement towards the sustainability of space operations.

Endorsing entities are categorized by type as follows: email editor@talksatellite.com for full document.