| Acronym | Meaning |
| VTVL | Vertical Takeoff Vertical Landing |
| PM | Pressurized Module |
| KPNO | Kitt Peak National Observatory |
| CNES | Centre National D'Etude Spatiales |
| INTELSAT | International Telecommunications Satellite |
| ERS | Environmental Research Satellite |
| GSO | GeoSynchronous Earth Orbit |
| MB | Manned Base |
| NPOE | NPO Energiya |
| SPS | Solar Power Satellite |