Touch is tiring in space.
Abstract from "Touchscreen Usability in Microgravity" by Jurine A. Adolf and Kritina L. Holden, Proceedings of the CHI 96 Conference on Human Factors in Computing Systems:
Touchscreen technology is well-suited for extreme environments, for example, microgravity. However, the usability of touchscreens has not been tested in this environment. The Human Factors and Ergonomics Laboratory (HFEL) at the NASA Johnson Space Center has conducted three evaluations of touchscreen usability both in a simulated weightless environment and on a space shuttle mission. Preliminary findings suggest that touchscreens were preferred for those tasks with larger touch areas, but not for precise positioning. Not anticipated though was the hand fatigue experienced by astronauts. Complete results will be available.
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