STS-41B

space shuttle mission

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July 19, 2026

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STS-41B was a mission of the Space Shuttle Challenger that launched on February 3, 1984, and landed on February 11, 1984. The mission's primary objectives included deploying two commercial communications satellites and testing the Manned Maneuvering Unit (MMU) for the first time. Astronauts Bruce McCandless II and Robert L. Stewart successfully used the MMU to perform untethered spacewalks, demonstrating the capability for astronauts to move freely in space. The mission also carried the first European Space Agency astronaut, Ulf Merbold, into orbit.12

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Ronald McNair
…first spaceflight was on the STS-41B mission of the space shuttle Challenger (February 3–11, 1984). During that flight astronaut Bruce McCandless became the first person to perform a space walk without being tethered to a spacecraft. McNair operated the shuttle’s robotic arm to move a platform on which an astronaut…
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…first spaceflight was on the STS-41B mission of the space shuttle Challenger (February 3–11, 1984). During that flight astronaut Bruce McCandless became the first person to perform a space walk without being tethered to a spacecraft. McNair operated the shuttle’s robotic arm to move a platform on which an astronaut…
Read More