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Karen Nyberg earned her Ph.D. in mechanical engineering from The University of Texas at Austin in 1998, studying human thermoregulation and control of thermal neutrality in spacesuits.
As a mission specialist and flight engineer, she took her first voyage on the Space Shuttle Discovery in 2008. Nyberg was one of just two women in space when she launched on a Russian Soyuz spacecraft in 2013, and spent 166 days working at the International Space Station.
Her down-to-earth videos showed viewers how to wash your hair and how to run on a treadmill without gravity. Her biggest challenge: quilting in space.