In 1962, most southern cities had a downtown hotel barbershop. One beautiful spring morning, I went downtown for a haircut. The shop was crowded, and Dr. Wernher von Braun sat down next to me. I knew he led the team building the Saturn rockets destined to send Americans to the Moon. He didn't know me, but he started talking to me anyway. He was curious about everything: what classes I had taken in college, the subjects that were covered, and of course, my grades. He asked if I'd ever thought about working in the space program. I answered no. He said I should consider it, gave me a name and phone number of someone at the Marshall Space Flight Center, and told me to call if I decided to look into a career in rocketry.
Not long after that, I decided to go for it. I called Marshall! I was interviewed and started work in 1962 in the Center's Aeroballistics Laboratory. I used my math and physics skills to analyze how the Saturn rockets would behave as they lifted off and flew into orbit. What I remember about those early days is that we were racing against time and the Soviets. We all remembered the noisy beep of the Sputnik satellite as it passed overhead, an annoying reminder that we were behind.
I saw many rocket tests -- some which even shook the windows in North Alabama. Every rocket engine firing signaled we were making progress. It wasn't just a matter of landing men on the Moon. We wanted to show that America -- a democracy -- was the technological leader of the world. On July 20, 1969, we watched as the first man stepped on the Moon. As part of six Apollo missions, we saw 12 men walk on the Moon. They have been the only people to explore the Moon. The last Americans left the Moon in December 1972.
Von Braun and his team inspired me. Now, I share my knowledge with young engineers who are designing spacecraft and discovering new technologies that will take us back out into the solar system. Today's young engineers are as smart and dedicated as the Apollo team who built the Saturn V -- still the largest rocket ever built. They are using everything we've learned and combining it with modern technologies and materials. And this time, it is not a race. It is a journey.
To propel people, robots, and telescopes on voyages across the universe, launch vehicles must be big heavy-lifters, but they also must be safe and affordable. Building rockets is never easy. Over the years, we've learned that when things go wrong, the space environment is dangerous and cruel. To get off the ground, rockets harness a tremendous amount of power -- the smoke and fire that makes my heart race every time I see a rocket launch. Taming that fire is one of most exciting things about rocket science.
Rockets are the tools of exploration. Their very existence dares us to dream and turn those imaginings into exciting adventures. Over the years, I have participated in studies that examined the best way for humans to travel to Mars and other places. Most recently, I was part of a team that studied more than 2,000 concepts for heavy-lift launch vehicles that could send humans and cargo on many different types of missions. These heavy-lifters -- taller than 30-story buildings and so wide that a semi-truck could drive inside the fuel tanks -- can hold enough fuel to travel deeper in space and carry the equipment needed for human and robotic exploration.
The first 50 years at NASA have been fun. In the next 50 years, I hope my grandchildren witness Americans going even farther out into space, exploring the universe, and bringing new knowledge home to Earth.