Sally K. Ride, the first American woman to enter space, died today of pancreatic cancer. She was 61.

Ride joined NASA in 1978 after answering a newspaper ad. She rose to fame in 1983 when she was a mission specialist aboard the Space Shuttle Challenger. At 32, Ride was also the youngest American to go into space. Ride would go into space on the Challenger for a second time the following year. She was due to fly on Challenger again but it was, of course, destroyed on an ill-fated mission in 1986. Ride served on the panel investigating the Challenger accident. She would also be appointed to the panel which investigated the 2003 Columbia accident.

Since Ride went into space nearly thirty years ago, 42 American women have followed suit.

In 2001, she founded Sally Ride Science which is dedicated “to supporting girls’ and boys’ interest in science, math and technology.”