File:Astronaut McCandles during Extra Vehicular Activity 001.jpg

Summary
Astronaut Bruce McCandless II, mission specialist, participates in a extra-vehicular activity (EVA), a few meters away from the cabin of the shuttle Challenger. He is using a nitrogen-propelled hand-controlled manned maneuvering unit (MMU). He is performing this EVA without being tethered to the shuttle. The picture shows a cloud view of the earth in the background.