Discretionary Spending

Function 250 - General Science, Space, and Technology

Eliminate Human Space Exploration Programs

CBO periodically issues a compendium of policy options (called Options for Reducing the Deficit) covering a broad range of issues, as well as separate reports that include options for changing federal tax and spending policies in particular areas. This option appears in one of those publications. The options are derived from many sources and reflect a range of possibilities. For each option, CBO presents an estimate of its effects on the budget but makes no recommendations. Inclusion or exclusion of any particular option does not imply an endorsement or rejection by CBO.

Billions of Dollars 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2017-2021 2017-2026
Change in Spending                        
  Budget authority 0 -8.5 -8.7 -8.9 -9.1 -9.3 -9.5 -9.7 -9.9 -10.1 -35.2 -83.5
  Outlays 0 -6.3 -8.5 -8.8 -9.0 -9.2 -9.4 -9.6 -9.8 -10.0 -32.6 -80.7

This option would take effect in October 2017.

The National Aeronautics and Space Administration’s (NASA’s) Human Exploration and Operations Mission Directorate oversees both the development of the systems and capabilities required to explore deep space and the agency’s operations in low-Earth orbit. The directorate’s human exploration programs fund the research and development of the next generation of systems for deep space exploration and provide technical and financial support to the commercial space industry. Complementing those efforts, the space operations programs carry out missions in low-Earth orbit, most notably using the International Space Station, and provide space communications capabilities.

This option would terminate NASA’s programs for human space exploration and space operations, except for those necessary to meet space communications needs, such as communication with the Hubble Space Telescope. (The agency’s science and aeronautics programs and robotic space missions would continue.) Eliminating those human space programs would save $81 billion between 2018 and 2026, the Congressional Budget Office estimates.

The main argument for this option is that increased capabilities in electronics and information technology have generally reduced the need for humans to fly space missions. The scientific instruments used to gather knowledge in space today rely much less (or not at all) on nearby humans to operate them. NASA and other federal agencies have increasingly used robots to perform potentially dangerous missions in order to avoid putting humans in harm’s way. For example, NASA uses remotely piloted vehicles to track hurricanes over the Atlantic Ocean. Those vehicles are able to operate at much higher altitudes than conventional tracking aircraft without exposing pilots to the dangers presented by severe storms.

Eliminating humans from spaceflights would avoid risk to human life and would decrease the cost of space exploration by reducing the weight and complexity of the vehicles needed for the missions. (Unlike instruments, humans need water, air, food, space to move around in, and rest.) In addition, by replacing people with instruments, one-way missions would be possible, thus eliminating the cost and complexity of return and reentry into the Earth’s atmosphere. Return trips would be necessary only when a particular mission required it, such as to collect samples for further analysis.

A major argument against this option is that eliminating human spaceflight from the orbits near Earth would end the technical progress necessary to prepare for human missions to Mars (though such missions are—at a minimum—decades away). Moreover, if robotic missions proved too limiting, then human space efforts would have to be restarted. Another argument against this option is that there may be some scientific advantage to having humans at the International Space Station to conduct experiments in microgravity that could not be carried out in other, less costly, ways. (However, the International Space Station is currently scheduled to be retired in 2024; its decommissioning was twice postponed, first from 2015 and then from 2020.)