"Mystery creates wonder and wonder is the basis of man's desire to understand."

"It's a brilliant surface in that sunlight. The horizon seems quite close to you because the curvature is so much more pronounced than here on earth."

"I believe that every human has a finite number of heartbeats. I don't intend to waste any of mine running around doing exercises."

"Knowledge is fundamental to all human achievement and progress. It is both the key and the quest that advances mankind. The search for knowledge is what brought men to the moon; but it took knowledge …"

"It is a grand and glorious day to be an American."