S83-45520 (December 1983) --- The space shuttle Challenger, making its fourth spaceflight, highlights the 41B insignia. The reusable vehicle is flanked in the oval by an illustration of another PAM-D assisted satellite deployment; and astronaut making the first non-tethered extravehicular activity (EVA); and eleven stars. The crew member at right is equipped with the manned maneuvering unit (MMU), a debuting backpack/motor apparatus allowing for much greater freedom of movement than that experienced by any previous space travelers performing EVA. Surnames of the five astronaut crew members balance the Robert McCall artwork. They are Vance D. Brand, Robert L. Stewart, Bruce McCandless II, Ronald E. McNair, Robert L. Gibson. The flight is scheduled for a launch in early 1984. The NASA insignia design for space shuttle flights is reserved for use by the astronauts and for other official use as the NASA Administrator may authorize. Public availability has been approved only in the forms of illustrations by the various news media. When and if there is any change in this policy, which is not anticipated, the change will be publicly announced. Photo credit: NASA