Kathryn D. Sullivan
The first American woman to walk in space, and later the first person to also touch its deepest opposite
Kathryn Sullivan trained as a geologist and oceanographer before being selected in 1978 as part of NASA's first astronaut class to include women, a group that trained together against a backdrop of institutional uncertainty about how, or whether, spaceflight procedures needed to change for a mixed-sex crew. She flew on three Space Shuttle missions over the following decade.
On her first mission in October 1984 she became the first American woman to perform a spacewalk, working outside the shuttle to test a satellite refuelling system, a task that required functioning calmly for hours in a pressurised suit with no margin for equipment failure. On a later mission in 1990 she was part of the crew that deployed the Hubble Space Telescope, one of the most significant scientific instruments ever placed in orbit.
After leaving NASA she moved into ocean and atmospheric science administration, eventually serving as head of the National Oceanic and Atmospheric Administration, a role that drew directly on her original scientific training rather than her fame as an astronaut. She could easily have treated her flying career as the high point of her working life and stopped there.
Instead, in June 2020, in her late sixties, she joined an expedition aboard Victor Vescovo's submersible and descended to the Challenger Deep, the lowest point of the ocean, becoming the first woman to reach it and the first person in history to have both walked in space and reached the deepest point on Earth, a pairing of extremes that no one had previously combined in one career.