First untethered spacewalk
Who
Bruce McCandless
What
first first
Where
Unzutreffend (low Earth orbit)
When

NASA astronaut Capt. Bruce McCandless II, USN (b. 8 Jun 1937), was the first person to perform an untethered spacewalk from the space shuttle Challenger, on 7 Feb 1984. His spacewalk was a successful test of the Manned Maneuvering Unit.