In No Dream Is Too High: Life Lessons from a Man Who Walked on the Moon, Apollo astronaut Aldrin shares some of his guiding principles.

What was the most surprising thing about the Apollo 11 mission? Your favorite memory?

I had my own firsts on the moon. I was the first to pee on the moon! And actually I was the one to speak the first words on the moon: “Contact light, okay, engine stop.” When the engine-arm circuit breaker in our lunar module broke, I had to use some out-of-the-box thinking—using a pen to fix it.

You reprint President Nixon’s contingency speech for Apollo 11 in the book. What was it like to read that after the fact?

I would have been extremely surprised if they hadn’t had a speech prepared in the event we didn’t make it back. It would have been irresponsible. We all knew the risks and we were prepared to take them. But we had estimated—me, Mike [Collins], and Neil [Armstrong]—that we had a 60% chance of successfully landing on the moon. We could always abort and come back if there was something wrong. But we felt we had a 95% chance of returning home safely. We liked those odds.

You offer many important lessons in this book. Which do you think is the most important and why?

Maintain your sense of adventure. It is what keeps you young, leads you to new challenges, tests your instruments and your guts, creates events to make you laugh, and leads you to meet people of all walks of life.

You’ve lived your own advice—maintaining your spirit of adventure. What is your next challenge and why?

I will always be known as the second man on the moon. I want to be remembered for more than kicking up some dust on the moon. My motivation is to continue to serve my country, a vow I took at West Point at the age of 17 and take just as seriously today. My goal is to be remembered for having planned and enabled a permanent settlement on Mars. But public apathy doesn’t help. So why do I go on shows like Dancing with the Stars? Or 30 Rock? Hopefully, people see this guy who walked on the moon and wonder what else I’m up to these days. And then they see that hey, he’s planning Cycling Pathways to Occupy Mars. I still have much to add to my legacy. You ain’t seen nothing yet!