Ride, the first American woman in orbit, died Monday at her home in the San Diego community of La Jolla at age 61. The cause was pancreatic cancer, an illness she had for 17 months, according to her company, Sally Ride Science.
Ride rode into space on the space shuttle Challenger on June 18, 1983, when she was 32. Since then, 42 other American women flew in space.
"Sally was a national hero and a powerful role model. She inspired generations of young girls to reach for the stars," President Barack Obama said in a statement.
When shuttles started flying frequently with crews of six or seven, astronauts became plentiful and anonymous. Not Ride.
"People around the world still recognize her name as the first American woman in space, and she took that title seriously even after departing NASA," Eileen Collins, the first female space shuttle commander, said in a statement. "She never sought media attention for herself, but rather focused on doing her normally outstanding job."
When Ride first launched into space, feminist icons such as Gloria Steinem and Jane Fonda were at Kennedy Space Center and many wore T-shirts alluding to the pop song with the refrain of the same name: "Ride, Sally Ride."
NASA Administrator Charles Bolden, a former astronaut, said Ride "broke barriers with grace and professionalism - and literally changed the face of America's space program."
"The nation has lost one of its finest leaders, teachers and explorers," he said in a statement.
Ride was a physicist, writer of five science books for children and president of her own company, which motivates youngsters to pursue careers in science, technology, engineering and math. She had also been a professor of physics at the University of California, San Diego.
In 1978, NASA included women in the astronaut corps, selecting Ride and five other women to join the club, which had been dominated by male military test pilots. Ride beat out fellow astronaut candidates to be the first American female in space. Her first flight came two decades after the Soviets sent a woman into space. A second Soviet woman flew in space in 1982.
"On launch day, there was so much excitement and so much happening around us in crew quarters, even on the way to the launch pad," Ride recalled in a NASA interview for the 25th anniversary of her flight in 2008. "I didn't really think about it that much at the time - but I came to appreciate what an honor it was to be selected to be the first to get a chance to go into space."
Ride flew in space twice, both times on Challenger, in 1983 and on October 5, 1984, logging 343 hours in space. A third flight was cancelled when Challenger exploded in 1986. She was on the commission investigating that accident and later served on the panel for the 2003 Columbia shuttle accident, the only person on both boards. She also was on the president's committee of science advisers.
The 20th anniversary of her first flight also coincided with the loss of Columbia, a bittersweet time for Ride, who discussed it in a 2003 interview with The Associated Press. She acknowledged it was depressing to spend the anniversary investigating the accident, which killed seven astronauts.
"But in another sense, it's rewarding because it's an opportunity to be part of the solution and part of the changes that will occur and will make the program better," she said.
Later in the interview, she focused on science education and talked about "being a role model and being very visible."
"She was very smart," said former astronaut Norman Thagard, who was on Ride's first flight. "We did have a good time."
It was all work on that first flight, except for a first-in-space sprint around the inside of the shuttle, Thagard recalled in a phone interview Monday. He didn't know who won.
Born on May 26, 1951, in Los Angeles' San Fernando Valley, Ride became fascinated with science early on, playing with a chemistry kit and telescope. She also excelled in tennis and competed in national junior tournaments.
She earned bachelor's degrees in physics and English from Stanford University in 1973 and a master's in 1975. She was studying for a Ph.D. when she saw an ad in the student newspaper calling for scientists and engineers to apply to become astronauts. She was chosen in 1978, the same year she earned her doctorate in physics from Stanford.
Ride was married to fellow astronaut Steve Hawley from 1982 to 1987. Hawley said Ride was never fully comfortable being in the spotlight.
"While she never enjoyed being a celebrity, she recognized that it gave her the opportunity to encourage children, particularly young girls, to reach their full potential," Hawley said in a statement released by NASA.
One of Ride's last legacies was allowing middle school students to take their own pictures of the moon using cameras aboard NASA's twin Grail spacecraft in a project spearheaded by her company.
"Sally literally could have done anything with her life. She decided to devote her life to education and to inspiring young people. To me, that's such a powerful thing. It's extraordinarily admirable," said Maria Zuber, a professor at the Massachusetts Institute of Technology who heads the Grail mission.
Ride's office said she is survived by Tam O'Shaughnessy, her partner of 27 years and a co-founder of Sally Ride Science; her mother, Joyce; her sister, Bear, a niece; and a nephew.
Science Writer Alicia Chang contributed to this report from Los Angeles.