Views of the extravehicular activity during STS 41-B

This iconic photo shows astronaut Bruce McCandless floating above the curve of the earth on NASA’s first untethered spacewalk.

Though it looks like it could be a still from Hollywood’s latest space thriller, this image was taken during the 10th NASA Space Shuttle Mission in 1984. McCandless and fellow astronaut Robert L. Stewart were tasked with testing the new Manned Maneuvering Unit (MMU). While Stewart stayed fairly close to the ship, McCandless ventured out 320 feet from the orbiter, leading to this image taken by Robert Gibson.

Though the MMU was retired just a few years later, this image lives on as a symbol of the bravery of NASA’s astronauts and a representation of just how small we are in the universe and how much there is still to know.