Policy options to address collision risk from space debris (report)
Decades of near-Earth space exploration and utilisation have resulted in an increasingly congested environment. As a by-product of space missions, a wide range of non-functional objects, from entire satellites to small bolts, have been deposited in orbit. These pieces of space debris are a growing threat to space assets, human spaceflight and future access to outer space. Making space activities sustainable, i.e., ensuring that benefits from access to and use of space meet the needs of the present without compromising the ability of future generations to meet their needs, requires informed policy discussion about matters related to space debris.
This policy brief provides a range of policy options to improve the assessment, evaluation and management of collision risk, as well as its communication. It draws on discussions held at a multi-disciplinary and multi-stakeholder expert workshop organised by the EPFL International Risk Governance Center (IRGC) in May 2021 and on follow-up exchanges with space debris experts. As low Earth orbit (LEO) is the region of space with the largest collision risk, it is the focus of this policy brief. However, some of the policy options proposed can be readily applied to other orbital regions.
There is insufficient evidence available necessary for a comprehensive scientific assessment of the risk. There is also an incomplete evaluation of the possible response strategies, which impedes the prioritisation of policy options to avoid, reduce or mitigate the risk. IRGC’s opinion is that a complete evidence-based evaluation of the risk, response options and associated cost is still missing. Reasons for this include uncertainties about the future behaviour of space actors (such as the number and orbits of satellites launched), the implementation of non-binding guidelines (such as the rate of successful post-mission disposal), and the costs/benefits of mitigation and remediation approaches (such as the cost of active debris removal). However, IRGC’s opinion is that incomplete assessment should not delay action. The development and deployment of technology to manage the risk and the implementation of best practices should be encouraged and rewarded, including through economic incentives.
We currently have a limited understanding of the maturity of certain technologies, as well as their capacity to scale up and be cost-effective under various possible policy and regulatory decisions. Moreover, the long timescale on which the issue unfolds makes the elaboration of cost-effective requirements and best practices difficult. Given the importance of the growing space economy and the extent of adverse consequences if certain risks materialise (e.g., cascading collisions in certain orbits limiting or preventing their use, the loss of particularly valuable spacecraft disrupting services on Earth), it would be a mistake to adopt a wait and see approach until much more granular evidence relevant to policy decisions becomes available. Governments should become more active, starting with incentives to produce the evidence needed for a more comprehensive risk assessment and the evaluation of possible response strategies.
This policy brief addresses the following four areas where policy decisions can support efforts to better address collision risk.
