4.5. Ground Support
   4.5.1. Mission Control Facilities
   4.5.2. Ground Support Communications
   4.5.3. Mission Support Functions
      4.5.3.1. Guidance, Navigation, and Control
      4.5.3.2. Communications
      4.5.3.3. Electrical Power
      4.5.3.4. Thermal Control
      4.5.3.5. Environmental Control & Life Support
      4.5.3.7. Structures & Mechanisms
      4.5.3.8. Extravehicular Activity
      4.5.3.9. Propulsion
      4.5.3.10. Mission Equipment
      4.5.3.11. Test & Verification
      4.5.3.12. Spacecraft Video