First Untethered Spacewalk by Bruce McCandless II

Bruce McCandless II conducted the first untethered spacewalk during NASA's STS-41-B mission. This event marked a pivotal advancement in space exploration, showcasing the capabilities of astronauts to operate independently of their spacecraft. The spacewalk was facilitated by the use of a new device known as the Manned Maneuvering Unit (MMU), which allowed McCandless to navigate freely in the vacuum of space. During the mission, he was able to travel distances of up to 100 meters from the Space Shuttle Challenger, demonstrating the potential for astronauts to perform tasks in space without being physically connected to their vehicles. This capability opened new avenues for future missions, including satellite repairs and other extravehicular activities that require greater mobility and flexibility. The successful execution of this spacewalk not only highlighted the technological advancements of the time but also set a precedent for subsequent missions involving untethered operations in space. The MMU was a significant innovation, as it provided astronauts with the ability to maneuver in three-dimensional space, which was previously limited to tethered operations. McCandless's spacewalk lasted approximately six hours, during which he conducted various tests and experiments, further contributing to the understanding of human capabilities in space environments.