Curiosity is the essence of human existence. 'Who are we? Where are we? Where do we come from? Where are we going?' I don't know. I don't have any answers to those questions. I don't know what's over there around the corner. But I want to find out.

To become an astronaut, someone has to have a dream of his own to do something that he or she has always wanted to do, then commit himself to making that dream come true.

After Apollo 17, America stopped looking towards the next horizon. The United States had become a space-faring nation, but threw it away. We have sacrificed space exploration for space exploitation, which is interesting but scarcely visionary.

Get the shuttle out of the garage. It's in its prime of its life. How could we just put it away?

If the guidance failed or started to stray or went somewhere we didn't like or the ground didn't like, I could flip a switch, and I could control seven, over seven and a half million pounds of thrust with this handle and fly the thing to the Moon myself.

We will certainly see teachers, journalists, artists and poets in space. Whatever it takes to the be the best is what it will take to get you into space.

It's our destiny to explore. It's our destiny to be a space-faring nation.