Dr. Sally Kristen Ride (born May 26, 1951) from Los Angeles, California, is an American (United States) physicist and a former NASA astronaut. She studied at Portola Middle School (Portola Middle School (Tarzana)), Westlake School for Girls, Swarthmore College and Stanford University, and earned a masters degree and PhD (Doctor of Philosophy). Ride joined NASA in 1978, and in 1983, became the first American woman, and then-youngest American, to enter space (Low Earth orbit). In 1987 she left NASA to work at Stanford University Center for International Security and Arms Control (Center for International Security and Cooperation).