Image (a): a non-Keplerian orbit for asteroid global mapping called resonant terminator orbit (RTO), offering a wider variety of lighting conditions than traditional terminator orbits such as those used in the OSIRIS-REx mission while naturally avoiding eclipses due to the orbiting body. This type of orbit exists under strong solar radiation pressure (SRP) around small asteroids, such as Bennu, Itokawa, and Ryugu. This is a good example of leveraging non-Keplerian orbital dynamics to design unconventional orbits with higher scientific benefits. See Risk-aware Mission Design for In situ Asteroid Exploration under Uncertainty to learn more about how we could perform maintenance of this type of orbits under various uncertainty

Image (b): a science orbit designed for the Psyche mission, a NASA's Discovery mission. The orbit is designed to have small drifts of beta angle over time (beta angle: angle formed by the sunlight and the spacecraft orbital plane) by applying the method of orbital averaging. Frozen-beta orbits and their variants are studied by using singly-averaged and doubly-averaged dynamics. See Science orbit design with a quasi-frozen beta angle: effects of body obliquity on J2-perturbed dynamics for more detail

See Dynamical Systems in Spaceflight for more detail on our research on dynamical systems for spaceflight