The United States has built and operated two space stations that have provided a sustained human presence in low Earth orbit (LEO): Skylab, which orbited from 1973 to 1979, and the International Space Station (ISS), which has operated from 1998 to the present. The ISS was at one point scheduled to be retired in 2015 to help fund the Constellation program, but its operational life has been extended until 2024; its life could be extended to 2028 before major subsystems would potentially have to be overhauled or replaced. After retirement, the ISS might be deconstructed, with elements possibly made available for use by follow-on space stations into the 2030s.
The impending retirement of the ISS poses important questions about continued U.S. human presence in LEO for scientific, technological, and geopolitical reasons. Could the future of sustained U.S. human presence in LEO in the post-ISS era be built on the foundation of private sector efforts? Could commercial markets emerge that are large enough to support private space stations in LEO? Or will governments, at home or abroad, continue to be the primary owners, operators, and customers for space stations in LEO?
The purpose of this evaluation is to determine whether a private space station could cover operations and capital costs given current expectations about the likely size of potential future markets for their services. We strove specifically to understand the market for services provided by private space stations in LEO, and assess whether this market is likely to generate adequate revenues from such services to cover the fixed and operations costs of a space station owned and operated by the private sector.
For the purpose of this study, conducted between May and October 2016, we assumed that a private space station would be wholly owned and operated by private parties who would decide the station's capabilities, the markets it would serve, and the prices it would charge for its services. The private parties' customers could be commercial or government entities whoever would be willing to pay for the services. Additionally, we assumed that the space station needs to be human-tended or human-inhabited, located in LEO, and able to engage in many revenue-generating activities.