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Rachael Seidler

Rachael Seidler, University of Florida

American astronaut Bruce McCandless II photographed from the Space Shuttle Challenger during the first untethered EVA, made possible by his nitrogen jet propelled backpack (Manned Manuevering Unit or MMU), 7th February 1984. (NASA/Space Frontiers/Getty Images)

Spending time in space can harm the human body

Rachael Seidler