Space Sustainability in LEO: a multidisciplinary approach to identify and mitigate economic, operational and technological risks of active debris removal solutions

The launch traffic to Low Earth Orbit (LEO) is experiencing a significant increase, since LEO is enabling common use infrastructure critical for the ascent of the space economy. The intensifying commercial use of LEO and the space environment sustainability are subject of a growing discussion among policy makers. Moreover, the rapid increase of space debris is becoming of primary importance not only for international institutions but also for private companies. In the recent years, there have been several attempts to assess solutions to the orbits' overcrowding, e.g. through Active Debris Removal (ADR) de-orbit technology including net capture, sail, harpoon, laser system, adhesive magnets and single and multiple robotic manipulators. The current legal framework does not mention who should be in charge of removing debris, and the adoption of these technologies could cause accidents, instability and mistrust. Countries view any interference with their space assets or capabilities as serious national securitythreats. Many of these threats come in the form of Anti-Satellite (ASAT) capabilities, which can be used to deceive, deny, degrade, disrupt, or destroy space assets. For example, although ADR operations are not inherently ASAT activities, many of the technologies and techniques which are candidate for ADR purposes could also be used to damage or destroy a spacecraft, in an ASAT manner by considering the future scenarios, this paper aims at evaluating the risks associated with identified technologies, and their consequent level of attractiveness. First, the analysis assesses the current and oncoming solutions for debris removal and monitoring. Second, it evaluates the economic, political, and security risks that affect attractiveness of those technologies. To conclude, building on previous evidence, this paper dwell on public recommendations on how to guarantee the implementation of the identified technologies, while mitigating the associated risks, so to ensure safety, security and sustainability of the space environment.