As other types of human activities, the exploration and use of outer space causes a variety of environmental consequences. Although some of the risks involved have been understood only recently, the international community has long known that space activities contribute to environmental degradation. The protection of the outer space environment is still considered inadequate due to the increasing development of space activities also by private actors, the renewed interest in space exploration and the desired objective of the sustainability in outer space.
A tool to mitigate and prevent harmful consequences of human activities is the prior assessment of their potential impact on the environment. Despite its success in many fields on Earth, as well as for extra-terrestrial activities (e.g. launching rockets and space objects re-entry), environmental impact assessment (EIA) is currently not a well-established tool in the international legal framework applicable to outer space activities. Hence, the rules of international environmental law constitute an important gap-filler for finding legal solutions to the main needs in this area.