Astronaut Bruce McCandless and the First-Ever Untethered Space Walk
On Feb. 7, 1984, astronaut Bruce McCandless ventured further away from the confines and safety of his ship than any previous astronaut had ever been, notes the caption to the above photo on NASA.gov. This space first was made possible by a nitrogen jet-propelled backpack, previously known at NASA as the Manned Maneuvering Unit or