Editor's note: Kathryn Sullivan, former astronaut and the first American woman to walk in space, is assistant secretary of commerce for environmental observation and prediction and deputy administrator for the National Oceanic and Atmospheric Administration. She is also serving as NOAA's acting chief scientist.
(CNN) -- Retrospectives of Sally Ride's life over the next few days are likely to include the words "ground-breaking," "trailblazer," "inspiration" and "mentor." And rightly so. She epitomized these words and so many more. To me, she was also a classmate, a crewmate, a collaborator and a friend.
Sally and I first crossed paths in the first grade at Hayvenhurst Elementary School in California in 1958, though neither of us remembered the other clearly. We had a good laugh as we pieced this together 20 years later, when we met as two of the first six women in NASA's astronaut corps.
It wasn't the only similarity in our backgrounds. We shared a love for competitive sports, and our college careers revealed that we both loved arts and letters as much as the sciences. The second point paid many dividends later on, in great crossword challenges during crew quarantine and many shared lecture engagements.
We six women in the Class of 1978 ranged in age from 39 (Shannon Lucid) to 26 (Sally and me). Underneath our different professional backgrounds and personal styles, we had many points in common: All six were intelligent, goal-oriented, creative and strong. We each had chosen our career path because it suited our talents and fired our passion, not in pursuit of celebrity.
But we found ourselves on a very different stage. We bonded as we took on the challenges that came with being the first six women in the U.S. astronaut corps, from the glare of the media spotlight to the everyday challenges of the workplace. We were keenly aware that what we did, and how we did it, would lay the ground for all the women who would come after us. We had to do it right.
Which is not to say we couldn't have fun while we were at it. Sally was one of the quickest wits and keenest pranksters in our class. She was the master of the clever, perfectly timed retort.
A favorite memory is from our first morning in orbit in 1984. Mission Control woke us up with the standard mix of a bit of music and words to the effect of, "Good morning, Challenger. Houston standing by." Instead of the normal response, "Roger," Sally launched into an answering machine reply: "We're sorry nobody can take your call right now. Please leave your name and number..." Our grins turned to guffaws when the Capcom replied with his name and a real phone number for Mission Control. We carried her joke on throughout the flight, with everyone taking turns at making up the morning's fake answering machine message.
"Why was Sally Ride tapped to fly first?" is a question I've been asked many times in the past few days. The truth is, none of us ever knew, not even Sally. Whatever the reasons may have been, history will record that the selection turned out well indeed. Sally performed superbly on STS-7 and stepped into the role of first American woman to fly in space with intelligence, dignity and grace.
With the distinction she earned in 1983, Sally was free to write her own ticket to life. That she chose to devote her energies to teaching and inspiring others to dream, to dare and to aspire to excellence speaks volumes about her character. She wanted to share her wonderment about the universe and joy of learning with others. She was committed to breaking down the cultural and educational barriers that block so many, especially young girls, from science and the opportunities it offers in life. And this she did, through her work as a physics professor, mentor, motivator and businesswoman.
Sally's place in history is solidly established by her many contributions to science, spaceflight and the American space program. But I daresay her greatest legacy lies in her post-NASA work as an educator and a role model.
She inspired countless people to reach for the stars Her spirit will live on in each and every one of them and in all of us who called her a friend.
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The opinions expressed in this commentary are solely those of Kathryn Sullivan.