Inside Orbiter Processing Facility 1 at NASA's Kennedy Space Center in Florida is being installed.

Inside Orbiter Processing Facility-1 at NASA's Kennedy Space Center in Florida, employees work within the aft end of space shuttle Discovery, where a replica shuttle main engine (RSME) is being installed.

This is the first of three replica engines to be installed. The work is part of the Space Shuttle Program’s transition and retirement processing of Discovery. Discovery is being prepared for display at the Smithsonian’s National Air and Space Museum, Steven F. Udvar-Hazy Center in Chantilly, Va. For more information, visit http://www.nasa.gov/shuttle. Photo credit: NASA/Jim Grossmann