Modeling Trajectory and Attitude to Optimize Baffle Design for the Optical Navigation System of the Emirates Mission to the Asteroid Belt

For the Emirates Mission to the Asteroid Belt (EMA) to successfully accomplish its objective of completing six asteroid flybys at distances up to 3.1 AU, an autonomous navigation system will be utilized to perform scientific operations. In Q1 of 2028, EMA plans to launch from Earth, heading to the main asteroid belt. The system's primary input is an optical navigation camera which must maintain a high enough signal-to-noise ratio (SNR) to accurately detect and track small, distant asteroids. This paper presents a detailed analysis that informs the baffle design for the optical navigation imager. The study leverages JPL’s SPICE Toolkit to model spacecraft attitude and positioning relative to the Sun and target asteroids. The use of celestial body ephemeris data and mission trajectory files allows for the computation of phase angle and other key design inputs. Using three-dimensional vector calculus, the analysis evaluates relevant vector orientations and angles in spacecraft body frame, identifying critical bounding cases of optical image degradation. The resulting baffle design leads to improved asteroid tracking accuracy, supporting mission success in this ambitious multi-asteroid mission. A robust framework for this geometric stray-light analysis is provided, allowing for rapid iteration and design for future missions.