What are the best methods and tools for orbital debris mitigation and removal?

1 Mitigation measures

The first step to address the orbital debris problem is to prevent or minimize its generation. This can be done by implementing mitigation measures that aim to reduce the launch and deployment of new objects, enhance the design and operation of spacecraft, and ensure the end-of-life disposal or reentry of spacecraft. Some of the widely adopted mitigation measures include the Inter-Agency Space Debris Coordination Committee (IADC) guidelines, the UN Space Debris Mitigation Guidelines, and the ISO standards on space debris. These measures provide recommendations and best practices for space actors to follow in order to reduce the potential for debris creation and collision.

2 Removal concepts

The second step to address the orbital debris problem is to remove or relocate existing objects that pose a high risk of collision or fragmentation. To do this, various methods and tools have been proposed or tested, such as tethers, nets, harpoons, lasers, and robots. Tethers are long and thin wires or cables that can attach to a debris object and use electrodynamic or momentum exchange forces to lower its orbit and speed up its reentry. Nets are flexible and deployable meshes that can wrap around a debris object and drag it down to a lower orbit or a controlled reentry. Harpoons are sharp and barbed projectiles that can pierce and hook a debris object and reel it in for disposal or relocation. Lasers are high-energy beams that can ablate or vaporize a debris object or impart a thrust force to change its orbit or attitude. Robots are autonomous or remote-controlled vehicles that can rendezvous and dock with a debris object and perform various actions such as grasping, pushing, pulling, or refueling.

3 Challenges and opportunities

The third step to address the orbital debris problem is to overcome the technical, legal, economic, and political challenges and seize the opportunities that arise from the development and implementation of removal concepts. Challenges include accurately locating, identifying, and monitoring the orbital debris population, as well as safely and reliably approaching, capturing, and controlling a debris object. Additionally, there must be justification and allocation of resources and funds for removal concepts. Opportunities include fostering innovation and collaboration among stakeholders while enhancing sustainability and security of the space environment. Furthermore, clearing orbital congestion can enable exploration and utilization of space, creating more space for new missions and applications.