In this historical 1961 photo from the U.S. space agency, Bob Oldrieve, a hot laboratory supervisor, uses manipulator arms to inspect radioactive materials within a hot cell. The pliers-type "hand" is visible inside the window. Operators became so skillful in operating the manipulators that some were even able to thread a needle with them.
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Each weekday, SPACE.com looks back at the history of spaceflight through photos (archive).