NASA confirmed her death Monday afternoon. Her office in San Diego said she died of pancreatic cancer.
Ride flew into space on the shuttle Challenger in 1983 when she was 32.
President Barack Obama is calling her a national hero and a “powerful role model”. In a statement, the president says Ride “inspired generations of young girls to reach for the stars” and “fought tirelessly to help them get there by advocating for a greater focus on science and math” in the nation’s schools.