David DeVorkin, Senior Curator, Collection: Astronomy and space sciences speaks during a press briefing at the new "Moving Beyond Earth," exhibition at the National Air and Space Museum in Washingon, Wednesday, Nov. 18, 2009. Moving Beyond Earth is an immersive exhibition that places visitors “in orbit” in the shuttle and space-station era to explore recent human spaceflight and future possibilities. Photo Credit: (NASA/Paul E. Alers)