As I step off at the surface at Taurus-Littrow, I'd like to dedicate the first step of Apollo 17 to all those who made it possible.

We don't have the capability today to put a human being in space of any kind, shape or form, which is absolutely, totally unacceptable when we got the greatest flying machine in the world sitting down at Kennedy in a garage there with nothing to do.

Curiosity is the essence of human existence.

Am I willing to go to Mars? Yes, but I'm not willing to spend nine months getting there, then wait 18 more months until the planets align to come home.

Today, we are on a path of decay. We are seeing the book close on five decades of accomplishment as the leader in human space exploration.

Chemical propulsion is obsolete to go anywhere other than the moon. Three days - that's acceptable. But for Mars, we need propulsion technologies to get us there in, say, 60 days - then spend whatever length of time we want to spend and return when we want to come home.

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.