In 1975, Dunbar was invited to participate in research at the Atomic Energy Research Establishment in Oxfordshire, as a visiting scientist. Her work there involved the wetting behavior of liquids on solid substrates. Following her work in England, she accepted a senior research engineer position with Rockwell International Space Division in Downey, California. Her responsibilities there included developing equipment and processes for the manufacture of the Space Shuttle thermal protection system in Palmdale. She represented Rockwell International as a member of the Dr. Kraft Ehricke evaluation committee on prospective space industrialization concepts. Dunbar completed her doctorate at the University of Houston in 1983. Her multi-disciplinary dissertation (materials science and physiology) involved evaluating the effects of simulated space flight on bone strength and fracture toughness. These results were correlated to alterations in hormonal and metabolic activity.