This iron-on decal from the NASA Kennedy Space Center is memorabilia of Apollo 17, the sixth and final human mission to land on the Moon. Launched on December 7, 1972, the mission carried Gene Cernan, Ron Evans, and Jack Schmitt to the Moon. The mission patch for Apollo 17 depicted on this decal was designed by Robert McCall, the famous space artist. Memorabilia like this iron-on decal would have been available for purchase at the Kennedy Space Center or from local vendors so that people could record their presence at the launch by having a memento to take home with them.
This object is not on display at the National Air and Space Museum. It is either on loan or in storage.