In 1984, U.S. astronaut Bruce McCandless made the first untethered space walk.
Bruce McCandless helped to develop the Manned Maneuvering Unit (MMU), a rocket-propelled backpack that was worn by an astronaut during shuttle spacewalks. During STS-41-B, aboard the Challenger space shuttle as a Mission Specialist, McCandless tested the MMU in spacewalks and thus became the first person to fly in space without being tethered to a spacecraft.
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