Crew-Aided Autonomous Navigation Project

Manual capability to perform star/planet-limb sightings provides a cheap, simple, and robust backup navigation source for exploration missions independent from the ground. Sextant sightings from spacecraft were first exercised in Gemini and flew as the loss-of-communications backup for all Apollo missions. This study seeks to procure and characterize error sources of navigation-grade sextants for feasibility of taking star and planetary limb sightings from inside a spacecraft. A series of similar studies was performed in the early/mid-1960s in preparation for Apollo missions, and one goal of this study is to modernize and update those findings. This technique has the potential to deliver significant risk mitigation, validation, and backup to more complex low-TRL automated systems under development involving cameras.