International space law, as part of the larger body of public international law, has always hinged upon the legal concept of the ‘State’ as the main relevant actor and carrier of direct rights and obligations. That concept has always been understood and defined with reference to States on Earth, which have been habitually defined in turn with reference to the sovereign control over territory on Earth as the most fundamental element of Statehood.
More recently, however, first a few major projects bent on exploitation of celestial bodies’ natural resources, and then various plans to establish more broadly long-term human habitats on the Moon (and later on perhaps also Mars) arose. In such a context, the age-old definition of a ‘State’ and ‘Statehood’ comes under pressure, and the question arises whether the concept of States should be adapted to a future reality of human habitation of non-terrestrial areas.