The 1961 launch of Yuri Gagarin into orbit around the Earth -- the birth of human spaceflight -- was a significant event for all peoples. It was a triumph of math, science, technology and engineering. It was a tribute to human ingenuity. It grew out of our collective curiosity about space, our sense of adventure, our willingness to take risks, and was empowered by our imagination. The human species took its first small, but daring step, off planet Earth. I believe its greatest impact and most enduring legacy is the inspiration it provides to future generations of explorers.