Sustainable missions to the Moon – Sustainability guidelines for lunar activities, a state-of-the-Art

Lunar endeavors are set to experience a substantial increase in the coming years, and interest is growing for long duration human missions on the Moon, in-situ resources utilisation, and commercially-oriented missions. All these expected activities lead to cast a spotlight regarding environmental sustainability, to avoid the same problems faced nowadays with space debris in near Earth orbits, and address new challenges linked with regular activities on the surface of other celestial bodies than Earth. This work aims to inform on the current and lacking guidelines in lunar orbit and on its surface. By comparing them with those for Earth, it is possible to identify the key aspects to which future space actors will have to pay attention to and which they will undoubtedly have to address. In particular, the state-of-the-art study focuses on satellite disposal options to prevent orbital crowding, fragmentation potential and surface impacts, as well as lunar landing, resulting in secondary fragmentation and lunar dust ejection. The final purpose is to be able to understand what it means to behave sustainably when it comes to lunar missions, in compliance with the principles of transparency and coordination of international space law, raising awareness among stakeholders and proposing solutions whenever feasible.