Another challenge is pollution control. Since the spacecraft will be equipped with a variety of imaging equipment, engineers must prevent adhesives, plastics and lubricants from generating gas. “We bake all the wiring before assembly, because once you put all the wraps on the wiring, the molecules leak out forever,” explains Perry. “After assembly, we also bake the finished wire harness as we add adhesives and other materials.”
Engineers also need to prevent biological contamination. An international treaty dating back to the early days of space exploration prohibits countries from introducing microbes from Earth to other worlds where life could harbor. During the assembly process, engineers regularly test harnesses for biological contamination. In addition, the finished seat belts are baked at 116°C for 25 hours. Once the harness is sterile, technicians must wear cleanroom clothing to work from then on.