Astronaut Kathryn D. Sullivan checks the latch of the SIR-B antenna in the space shuttle Challenger's open cargo bay during her historic extravehicular activity (EVA) on Oct. 11, 1984. This EVA marked the first space walk by an American woman, Dr. Sullivan went on to log more than 532 hours in space. Learn more about the generations of women who have worked, and are working to make the future happen across our space program at: women.nasa.gov Credit: NASA #NASA #astronaut #EVA #spaceshuttle #internationalwomensday #history #space #tbt