The Unlucky, Nine-Hour Spacewalk
A spacewalk is also called an extravehicular activity (EVA). During an EVA, astronauts exit the spacecraft to work on its exterior. The longest spacewalk was conducted in March of 2001 by astronauts Susan Helms and Jim Voss. They set out to relocate a component on the ISS exterior, and install a fixture on top of the station's U.S. Destiny laboratory. However, they encountered several difficulties, including tools that floated away into space and stubborn connectors that wouldn't come loose from the station's surface. The EVA clocked in at 8 hours and 56 minutes.
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from Smithsonian Channel
Key Facts In This Video
The Manned Maneuvering Unit (MMU) was essentially a jetpack that allowed astronauts to direct themselves in open space. (0:12)
Bruce McCandless performed the first untethered spacewalk 304 km (189 mi) above Earth. (0:51)
All NASA spacesuits now include a small open-space maneuvering unit, called SAFER: Simplified Aid For EVA Rescue. (1:51)