When astronaut Peggy Whitson pushed out of the International Space Station’s airlock on Tuesday morning, she was floating into history. Stipulated, Whitson was already a badass. But this extra-vehicular activity—an EVA, NASAspeak for a spacewalk—was Whitson’s 10th. That ties her for the American record. A PhD biochemist before she became an astronaut, Whitson has now spent more time in space outside a spacecraft than all but two other human beings.