English: Dr. John M. Logsdon visits NASA's Kennedy Space Center in Florida for a presentation to employees and a book signing of his newly released book "After Apollo? Richard Nixon and the American Space Program." Logsdon is professor emeritus at George Washington University's Elliott School of International Affairs, where he was the founder and long-time director of the university's Space Policy Institute. Over the years, he has assisted NASA by editing the NASA History Office's multi-volume series "Exploring the Unknown: Selected Documents in the History of the U.S. Civil Space Program" and by serving on the Columbia Accident Investigation Board and the NASA Advisory Council. Photo credit: NASA/Ben Smegelsky