Donna Shirley managed the Mars Exploration Program Office at the Jet Propulsion Laboratory and on July 4, 1997 the entire world watched as the Mars Pathfinder and the Sojourner Rover successfully landed on Mars. Two months later the Mars Global Surveyor successfully went into orbit around the red planet. Not only were these events two of the U.S. space program’s greatest successes, but they may well provide the world with some of the most important scientific data of the 20th and 21st centuries. According to Shirley, “My proudest moment was having my daughter, my second moment was when the Pathfinder and Sojourner actually worked. When you consider that it was going 17,000 miles an hour and it wasn’t supposed to make just another hole in the ground—well, that was a great achievement.” Donna Shirley retired in August 1998 as Manager of the Mars Exploration Program after a 32-year career at NASA’s Jet Propulsion Laboratory in Pasadena, California.