ORION ON-BOARD NAVIGATION ARCHITECTURE AND OPERATIONS CONCEPTS

The Orion navigation team is designing a navigation architecture incorporating advanced technology and new operations concepts, while facing challenges of low technological readiness levels, crew safety, and limitations in vehicle weight, available power, budget, and schedule. While Orion will fly the same flight phases as Apollo, there are important navigation differences between the programs. Optical tracking of lunar landmarks and stars will be performed automatically, rather than using Apollo era human-in-the-loop sextant tracking. On-board GPS orbit determination may be used in low Earth orbit to supplement ground radar tracking. GPS technology will be used to fly long-range lunar return skip entry trajectories that were not flown during crewed Apollo missions. Orion navigation will be more automated than navigation systems on previous NASA human flight vehicles and will require less crew interaction.