"Sally lived her life to the fullest, with boundless energy, curiosity, intelligence, passion, commitment, and love," says a statement on the Sally Ride Science website, which announced her death.
"Her integrity was absolute; her spirit was immeasurable; her approach to life was fearless."
On June 18, 1983, Ride captivated the nation when at age 32 she became not only the first American woman but also the youngest American to enter space aboard the Space Shuttle Challenger.
She traveled to space again aboard the Challenger the next year, and was later named to the Presidential Commission investigating the 1986 explosion of the shuttle just 73 seconds after takeoff, killing its seven crew members.
Ride worked at NASA headquarters as Special Assistant to the Administrator for long range and strategic planning before joining the University of California, San Diego, as a physics professor and director of the University of California’s California Space Institute.
'Broke Barriers'"Sally Ride broke barriers with grace and professionalism – and literally changed the face of America's space program," says NASA Administrator Charles Bolden. "The nation has lost one of its finest leaders, teachers and explorers. Our thoughts and prayers are with Sally's family and the many she inspired. She will be missed, but her star will always shine brightly."
Ride used her experience as an astronaut to encourage more women to get involved with science. In 2001, Ride founded Sally Ride Science, which develops science programs and publications from upper elementary and middle school students.
"My mission these days is to improve science education and particularly to encourage more girls and young women to go on in careers in science and math and technology or to at least explore the opportunities in those fields," Ride told members of the Allegheny County Women's Leadership Council in 2007.
"The philosophy we have is that we don't have to convert kids, even girls, to science. Let's just give them opportunities to explore those interests and show them that there are lots of other girls, normal kids, who share those interests and that there are lots of women who go on to careers that they love in science and engineering."
Ride is survived by her partner of 27 years, Tam O'Shaughnessy, along with her mother, sister and other family members.