Ride, Sally K. 1951-, American astrophysicist and astronaut, b. Encino, Calif. With a Ph.D. in physics from Stanford Univ., she joined NASA in 1978, where she was an astronaut (1979-87) and helped design the robot arm for the space shuttle. In 1983 she became the first American woman in space. She also served (1986, 2003) on the commissions that investigated the Challenger and Columbia disasters. In 1989 she became professor of physics and director of the California Space Institute at the Univ. of Calif., San Diego.