Sally Ride, the esteemed scientist, professor, and author best known as the first U.S. woman sent into outer space, died of pancreatic cancer on July 23. She was 61.

Ride’s numerous academic and professional achievements made her a pioneer and a role model for many, but she continually pursued what she referred to in a 1986 PW interview as her “personal crusade”: encouraging young people, especially girls, to study the sciences. In 2001, she founded Sally Ride Science, a San Diego-based education company that helps bolster children’s interest in science, math, engineering and technology.

Ride co-authored seven books for children: To Space and Back (with Susan Okie), and Voyager, The Third Planet, The Mystery of Mars, Exploring Our Solar System, Mission Planet Earth, and Mission: Save the Planet (all with her partner Tam O’Shaughnessy).

Simon Boughton, senior v-p and publishing director of the Macmillan Children's Publishing Group, worked with Ride and O’Shaughnessy on Voyager, The Third Planet, and The Mystery of Mars when he was at Random House/Crown, and on the 2009 Roaring Brook title Mission Planet Earth, a book about climate change. “In my experience, she took writing for children very seriously,” he says. “It was part of her mission to educate and excite kids – and especially girls – about the sciences. I had great respect for her as an author.”

Among the many tributes to Ride in recent days was an illustration by Micah Player featuring Lily, the globetrotting girl who inspires his Lately Lily children’s clothing line and who will star in a forthcoming line of books and gift items from Chronicle Books. The image of Lily in a space suit, saluting, was posted on Chronicle’s Facebook page and has since been shared via social media and appeared on a number of blogs and Web sites.