Stephanie Wilson was accepted into the astronaut training program by NASA in April 1996. She received a B.S. in Engineering Science from Harvard University in 1988, and a M.S. in Aerospace Engineering from the University of Texas, in 1992. After graduating from Harvard, Wilson worked for two years for the former Martin Marietta Astronautics Group in Denver, Colorado as a Loads and Dynamics engineer for Titan IV.

Following the completion of her graduate work, she began working for the Jet Propulsion Laboratory in Pasadena, California, in 1992. As a member of the Attitude and Articulation Control Subsystem for the Galileo spacecraft, Wilson was responsible for assessing attitude controller performance, science platform pointing accuracy, antenna pointing accuracy and spin rate accuracy.