This is a 1:15 scale model of the Atlas-Centaur rocket, used by the National Aeronautics and Space Administration to launch a variety of satellites and probes from 1962-1989. These rockets employed a modified Atlas D intercontinental ballistic missile first stage and a Centaur second stage. General Dynamics made this model and transferred it to NASM in 1983.
This object is on display in James S. McDonnell Space Hangar at the Steven F. Udvar-Hazy Center in Chantilly, VA.