Environmental Impact Assessment for Space Sustainability

As human settlements on celestial bodies and the exploitation of space resources become priorities for space-faring nations, the need to protect the sustainability of outer space is growing. States have begun introducing requirements to pursue sustainability in the use and exploration of outer space. This paper addresses environmental impact assessment (EIA) in the context of in-orbit activities. It provides an analysis of the obligations of states under the Outer Space Treaty (OST) and international environmental law to establish whether there is an obligation to conduct an EIA. To support this analysis, it reviews existing national regulations requiring an EIA. The aim is to determine how states have integrated EIAs into their regulatory frameworks and to clarify their scope, particularly whether EIAs must include impact on the outer space environment or only those on Earth. In addition, this paper provides a case study of the launch of the Starlink constellation to further highlight the need for EIA pertaining to in-orbit activities. While the obligation of performing an EIA for space activities is not likely to become customary international law, it is a resource that states can, and should, implement to achieve the sustainability of space activities.