| ARM | Asteroid Redirect Mission |
| ASPCO | Asian Pacific Space Cooperation Organization |
| ASTP | Apollo-Soyuz Test Project |
| ATV | Automated Transfer Vehicle |
| CAIB | Columbia Accident Investigation Board |
| CASIS | Center for the Advancement of Science in Space |
| DARPA | Defense Advanced Research Projects Agency |
| DOD | Department of Defense |
| DOE | Department of Energy |
| DRA | Design Reference Architecture |
| DRM | Design Reference Mission |
| ECLSS | environmental, control, and life support system (or systems) |
| EDL | entry, descent, and landing |
| ELIPS | European Programme for Life and Physical Science in Space |
| EM | Exploration Mission |
| EPO | Education and Public Outreach |
| ESA | European Space Agency |
| ETD | Exploration Technology Development |
| EVA | Extravehicular Activity |
| FY | fiscal year |
| GAO | General Accountability Office |
| GCR | galactic cosmic radiation |
| GER | Global Exploration Roadmap |
| GNP | gross national product |
| GPS | Global Positioning System |
| GSS | General Social Survey |
| HEOMD | Human Exploration and Operations Mission Directorate |
| HRP | Human Research Program |
| HTV | H-II Transfer Vehicle |
| ISECG | International Space Exploration Coordination Group |
| Isp | specific impulse |
| ISRU | in situ resource utilization |
| ISS | International Space Station |
| kW | kilowatt |
| L1 | Lagrangian point 1 |
| L2 | Lagrangian point 2 |
| LEAG | Lunar Exploration Analysis Group |
| LEO | low Earth orbit |
| LSAY | Longitudinal Study of American Youth |
| MEPAG | Mars Exploration Program and Analysis Group |
| MIT | Massachusetts Institute of Technology |
| MOL | Manned Orbiting Laboratory |
| MPCV | Multi-Purpose Crew Vehicle |
| MSL | Mars Science Laboratory |
| MT | metric ton |
| MW | megawatt |
| NASA | National Aeronautics and Space Administration |
| NCRP | National Council on Radiation Protection and Measurements |
| NEA | near-Earth asteroid |
| NEO | near-Earth object |
| NEP | nuclear electric propulsion |
| NERVA | Nuclear Engine for Rocket Vehicle Application |
| NRC | National Research Council |
| NRO | National Reconnaissance Office |
| NSF | National Science Foundation |
| NTP | nuclear thermal propulsion |
| OIG | Office of the Inspector General |
| SEP | solar electric propulsion |
| SLS | Space Launch System |
| SPE | solar particle event |
| STEM | science, technology, engineering, and mathematics |
| STG | Space Task Group |
| STMD | Space Technology Mission Directorate |
| Sv | Sievert |