Andrew Chaikin: I'm disappointed that I've remained so close to Earth! I wanted to go to the moon when I was five years old in 1961, and I still dream about it. I dearly miss the Apollo missions, but I feel extremely grateful that I could witness that era and then write about it years later. And it's not as if there's nothing to be excited about today. I still get a thrill from seeing the space station fly overhead and thinking about what it must be like to live up there. The robotic missions are also very exciting. It's really the sweep of space history, the continuous unfolding of exploration, that is so powerful to me, and that's what I'm trying to convey with this new book.

It was amazing to sit down with these men and hear their stories. I admire their bravery of course, but also their competence. They were all extremely capable, impressive human beings. I admire their intelligence they brought to their work, and the laser-beam focus. These guys could focus. What fascinated me were the personality differences. Some were extremely thoughtful; some were less so. Some talked very openly about the personal impact of going to the moon; for some it was a point of pride that they weren't affected by the experience. But that only made their stories more interesting.

I think the public perception of space has changed over the years. Back in the '60s everything was new and momentous, and it was difficult for most people to relate to the concept of going into space, or what astronauts did up there. Today space is much more familiar, but we're bombarded by information, and space is just a tiny part of that barrage. I don't think public interest ever completely goes away; it comes to the surface anytime something new and exciting happens. One of the top-20 moneymaking films right now is the new Space Station 3-D IMAX movie! People want to be inspired and amazed, and space does that, once they stop and think about it.

I spent about eight years in the trenches for A Man on the Moon, and nothing I've done since has been anywhere near as long or as difficult. Interviewing the astronauts, who were my childhood heroes, was the most exciting and fun part of the process. It was the writing that was tough, weaving all that information from those interviews, and from my research, into a narrative that would do justice to the subject. With this new picture-history, it was about six months of really intensive work. The fun part was choosing the pictures; the hard part was actually getting them all in hand, and then making sure they came out looking as beautiful as possible.

It's true that the spur of competition is what got us to the moon the first time. We spent all that money on Apollo because we wanted to beat the Soviets. When we won the moon race, the political impetus was gone. And the cost really made it politically unpopular. So, without a new political motive, it does come down to economics. Something has to happen to alter the equation. Either there has to be a "gold rush" in space, where something is discovered that is worth the cost of getting it, or someone has to figure out how to get into Earth orbit more cheaply. It still costs 10 thousand dollars per pound, which is the same as it was during Apollo.

I wouldn't say that science or scientists upset me; what does bother me is narrow-mindedness. I see it in doctors who won't consider any form of alternative medicine; I see it in biologists who claim that love is merely a chemical reaction in the brain; I see it in scientists who react negatively to a new theory because it upsets their own personal apple cart. We weren't given the incredible power of the human intellect so that we could decide to stop learning.

The astronauts say the Earth is the most beautiful sight they have seen. To me, the beauty of space exploration is not only what we see when we go beyond Earth, but the fact that we are clever enough and persistent enough to build space vehicles, and to fix them when they break. Space exploration is beautiful because it brings us face-to-face with a greater reality, and because it's the cutting edge of human evolution.

I would fund an effort to raise the public's consciousness with the space-age perspective we gained from the Apollo missions -- that we are all neighbors on a very beautiful and very precious Earth, and we'd better learn to live with each other, and take care of each other, and take care of our home in space. We owe it to the planet; we owe it to ourselves.

It shouldn't be an either-or question. Obviously it's essential to keep trying to find a cure for cancer, and an AIDS vaccine. And even if space exploration doesn't help us find those cures, it's still essential to the life of the human species, because when we stop striving to transcend our limits, we lose something that is quintessentially human. We lose the "mountaintop experience" that spaces gives us. Also, as Kennedy said, space exploration is inherently difficult, and it's good for us to do difficult things. But it's also possible that something we learn from exploring space will help us cure a disease, someday.

In the near term, I think the real hurdle is getting the space station completed, in spite of the budget problems, so that NASA can move on to other things. There are a lot of people within and outside NASA who are already thinking about some very exciting manned missions beyond Earth orbit, things that should be doable, like a mission to a near-Earth asteroid. It's never going to be "safe" to venture beyond our home planet, but that's not what exploration is about. We take worthwhile risks to gain something precious, whether it's knowledge, or experience, or perspective. And in the process, we become something greater than we were before.