It is hard to imagine that just 50 years ago, a young and vibrant President challenged a worried nation to reach for the seemingly impossible goal of landing humans on the moon and returning them safely to Earth. I was a teenager when President John F. Kennedy delivered his charge to Congress and the American people, but those words sparked my imagination, as they did for the millions of others who watched.

We recently completed the construction of the International Space Station and we stand at the door to closing the incredible 30 year Space Shuttle Era - a great adventure of unprecedented international cooperation in low Earth orbit. The words of President John Kennedy 50 years ago are at this time so appropriate: "...the impact of this adventure on the minds of men everywhere, who are attempting to make a determination of which road they should take."

He added, "Now it is time to take longer strides--time for a great new American enterprise--time for this nation to take a clearly leading role in space achievement, which in many ways may hold the key to our future on Earth."

And a NEW ERA began.

His inspiring words, calling on us to pursue exploration as a unified nation, to think beyond the moon and also envision the benefits of exploration for Earth, were part of a speech on "Urgent National Needs."

Today, we have another young and vibrant President who has outlined an urgent national need to out-innovate, out-educate, and out-build our competitors and create new capabilities that will take us farther into the solar system, and help us learn even more about our place in the universe.

President Barack Obama not only honors the Kennedy space legacy, but advances it for this new century with his vision for the next era of exploration and discovery. We stand at a moon shot moment once again, where we have a chance to make great leaps forward to new destinations, develop new vehicles and technologies, and new ways of exploring.

Our advantage now is that we have five decades of accomplishment and world leadership in space on which to build. The dreams President Kennedy helped make real for our world, and the dreams we still hold, may appear to be just out of reach but they are not out of our grasp.

We pause to remember the speech that launched that first moon shot moment, but we should not focus on the past. Later, we'll announce an exciting new mission that represents an important down payment on President Obama's exploration objectives.

We're making incredible progress in our goal to hand over low Earth orbit transportation services to our commercial partners, and yesterday, we announced an important next step in developing a successor to the space shuttle - a spacecraft that will carry our astronauts to new destinations away from the gravity of our home planet.

We are moving into a bright new future that builds on a challenge presented to us 50 years ago. It is important that we remember our history but we must always look forward toward a brighter future.

We want to express our thanks and appreciation to the entire Kennedy family for sharing this day with us, and I want to thank each of you who work every hour of every day to make NASA the world's preeminent space program. What began 50 years ago as a desperate race to space is now an ongoing journey to reach for new heights and new knowledge in the stars.

Charles Bolden is the Administrator of the National Aeronautics and Space Administration