Zimmerman Wins Clark School Dean’s Research Award

University of Maryland (UMD) Department of Aerospace Engineering alumna Grace Zimmerman (M.S. ’23) won first place in the 2023 Clark School Dean’s Research awards in the master’s category for her work exploring aeroassisted maneuvers for missions to the ice giants Neptune and Uranus.

Zimmerman, who graduated earlier this year with her M.S. from the department, is currently a part of the Astrodynamics and Control Systems Group at the Johns Hopkins Applied Physics Laboratory. There she supports the Parker Solar Probe and New Horizons missions.

While at UMD, Grace was a part of Associate Professor Christine Hartzell's Planetary Surfaces and Spacecraft Laboratory and was also a National Science Foundation Graduate Research Fellow.

Zimmerman’s thesis, which contributed to her winning work for the Dean’s award explored aerogravity-assisted trajectories for aerocapture at the ice giants, Neptune and Uranus.

Neptune and Uranus are two candidates for an aerocapture maneuver in which a spacecraft is captured into a bound orbit through a single atmospheric pass, explained Zimmerman.

Another aeroassisted maneuver, the aerogravity-assist (AGA), uses an atmospheric pass to increase the turn angle around a planet, thus enabling large changes in a spacecraft’s heliocentric velocity. As both maneuvers require high arrival velocities and thermal protection system technologies, it may be beneficial to execute both maneuvers on a single mission.

To investigate the possible benefit of an AGA trajectory for setting up an aerocapture maneuver at the ice giants, Zimmerman developed a two-layer optimization approach to investigate the trajectory space. Trajectories are identified for both Uranus and Neptune that increase the number of feasible launches as compared to traditional gravity-assisted (GA) trajectories. In addition, her study identifies a new family of periodic high-altitude AGA trajectories to Uranus that are feasible using existing vehicle technologies.

Zimmerman received her B.S. in Physics at the University of Central Arkansas. She has also completed multiple internships with NASA Goddard Space Flight Center and NASA Langley Research Center, where she worked on Uranus mission instrumentation, guidance and control for on-orbit robotics, and a guidance system for touch-and-go operations on small bodies.

She hopes to one day support a flagship mission to one of the ice giant planets.

Published December 19, 2023