Astronaut Kathy Sullivan poses for a picture with her space suit during a 1995 shuttle mission.
In this historical photo from the U.S. space agency, STS-31 Mission Specialist Kathryn D. Sullivan poses for a picture before donning her space suit and extravehicular mobility unit in the airlock of Discovery.
Onboard the April 25, 1990 shuttle mission that deployed the Hubble Space Telescope, Sullivan remained ready to do a spacewalk in case that there were problems putting the orbital observatory into space. The deployment went smoothly, and no spacewalk was necessary.
Each weekday, SPACE.com looks back at the history of spaceflight through photos (archive).