In February 1979, Ross was assigned to the Payload Operations Division at the Lyndon B. Johnson Space Center as a payload officer/flight controller, responsible for the flight operations integration of payloads into the Space Shuttle. Ross was selected as an astronaut in May 1980. His technical assignments since then have included: EVA, or "space walks", RMS (Remote Manipulator System, or "robotic arm"), and chase team; support crewman for STS 41-B, STS 41-C and STS 51-A; spacecraft communicator (CAPCOM) during STS 41-B, STS 41-C, STS 41-D, STS 51-A and STS 51-D; Chief of the Mission Support Branch; member of the 1990 Astronaut Selection Board; Acting Deputy Chief of the Astronaut Office, Chief of the Astronaut Office EVA and Robotics Branch, and Astronaut Office Branch Chief for Kennedy Space Center Operations Support. Ross was assigned to STS-62-A, the first Shuttle mission to launch from Vandenberg Air Force Base, but the mission was canceled after the Space Shuttle "Challenger" disaster.