Untethered space walkIn 1984, the first untethered spacewalks were made by Challenger astronauts Bruce McCandless II and Robert L. Stewart, each using a manned maneuvering unit (MMU), during the tenth flight of a Space Shuttle, mission 41-B, in orbit 150 nautical miles above the Earth. McCandless, with his MMU, was the first to leave the cargo bay, becoming the first person to fly free, untethered in space. Stewart also flew the MMU. They checked out the equipment, maneuvered within the cargo bay, flew away from and back to the orbiter, made docking exercises, recharged the MMU nitrogen tanks, and collected engineering data. These MMU flights demonstrated capabilities needed in the planned retrieval of the Solar Max satellite on a later shuttle mission.« |
