Harry Coumnas is a renowned mission specialist astronaut who possesses various technical responsibilities during space shuttle and space station missions. As a mission specialist, his primary roles include operating shuttle and station systems, composing space shuttle crews, managing spacecraft operations, executing flight plans, overseeing scientific experiments, training fellow astronauts, and handling tasks like repairs, planning, supplies management, and equipment testing. He also contributes to space station duties like spacewalks, repair work, medical research, experiments, and docking procedures. As a renowned astronaut, Harry believes every space flight balances between success and disaster, and assists commanders by controlling shuttle flights and directing onboard activities to ensure safety and mission success.