Alternative futures for crewed space cooperation after the international space station

Abstract

The International Space Station (ISS) has been the largest and most visible international space cooperation project for decades. The program began in the 1980s during the Cold War, incorporated Russia after the end of the Cold War, and has sustained permanent human occupancy in low Earth orbit for over 20 years. Although political support among the partners appears solid, it is uncertain how many more years the Station will be able to operate technically. The operating costs of the Station for the United States and international partners are considerable and have been increasing as the facility ages. These costs impose a constraint on the willingness and ability of international partners to participate in new human exploration efforts, such as Artemis, the European Space Agency (ESA) Lunar Village concept, and the International Lunar Research Station (ILRS) plans of China and Russia. Given the central importance of the ISS to international human spaceflight cooperation today, what are the possible alternative futures for crewed space missions in a post-ISS world? States and private sector actors could work to extend the ISS, participate in the Chinese Space Station, create multiple, smaller government and private human-tended platforms, focus on human missions to the Moon and Mars, or even cease participation in human space exploration altogether. This paper examines these alternatives futures, assesses the attractiveness and practicality of the alternatives to spacefaring states, and seeks to identify the key areas of technical, economic, and policy uncertainty that will shape the post-ISS era of human space exploration.