Kathryn Sullivan is the only person in history to have both floated in the vacuum of space and reached the crushing bottom of the Mariana Trench. This deep dive traces the completely original journey of a language-loving student who took science classes only to satisfy a college requirement and ended up making history in both directions.

We follow her pivot from linguistics to earth sciences, a fateful phone call about NASA recruiting women, and her choice of the space shuttle over a coveted submarine seat. From the first American woman’s spacewalk to engineering Hubble’s survivability and finally diving to the Challenger Deep, her career is a master class in systems thinking.

• The staggering coincidence of sharing a first-grade class with Sally Ride
• How she translated language-learning skills into reading rocks
• The real work of her spacewalk: orbital refueling with toxic hydrazine
• Championing captive bolts and modular design to keep Hubble serviceable
• Her 2020 dive to the deepest known point on Earth