STS-69 took place from September 7–18, 1995. Its prime objective was the successful deployment and retrieval of a SPARTAN satellite and the Wake Shield Facility (WSF). The WSF was designed to evaluate the effectiveness of using this free-flying experiment to grow semiconductors, high temperature superconductors and other materials using the ultra-high vacuum created behind the spacecraft, near the experiment package. Gernhardt was one of two astronauts to perform a spacewalk to evaluate future Space Station tools and hardware, logging 6 hours and 46 minutes of EVA. Mission duration was 260 hours, 29 minutes, and 8 seconds, traveling 4.5 million miles in 171 orbits of the Earth.