Mars is much closer to the characteristics of Earth. It has a fall, winter, summer and spring. North Pole, South Pole, mountains and lots of ice. No one is going to live on Venus; no one is going to live on Jupiter.

The decision to go to the moon is now appreciated and associated with President Kennedy's speech, but somebody else had told him it was a good idea. It turned out to be a good commitment, but it was a unique situation.

Tang sucks.

It's real easy to manufacture what you think the people want to hear. But that's not very honest.

I don't think we're going to build a 50-person spacecraft or a 100-person spacecraft.

The leader of an Earth organization who makes a commitment to history - of humans living on Earth, to begin permanent settlement/occupation of not the moon, but of another planet - this leader will have a legacy for history that will supersede Columbus, Genghis Khan or almost any recognized leader.

What's aero braking? That's a way to use the gravity and upper atmosphere of Earth to sling shot a ship out either deeper into space, or slow it down to be 'captured' by Earth's gravity.

Extraordinary observations require extraordinary evidence.

If we go back to the moon, we're guaranteed second, maybe third place because while we are spending all that money, Russia has its eye on Mars. Landing people on the moon will be terribly consuming of resources we don't have. It sounds great - 'Let's go back. This time we're going to stay.' I don't know why you would want to stay on the moon.

In space, you don't get that much noise. Noise doesn't propagate in a vacuum.

Unfortunately, kids are led to believe things are easier to achieve than they really are.

You need propellants to accelerate toward Mars, then to decelerate at Mars, again to re-accelerate from Mars to Earth, and finally to decelerate back at Earth. Accordingly, the mass of these required propellants, in short, drives our need for innovative launch vehicles.

I have no intention of selling any more of the historical Apollo 11 items in my possession for the remainder of my life. I intend to pass a portion of these items on to my children and to loan the most important items for permanent display in suitable museums around the country.

The first footfalls on Mars will mark a historic milestone, an enterprise that requires human tenacity matched with technology to anchor ourselves on another world.

The best way to study Mars is with two hands, eyes and ears of a geologist, first at a moon orbiting Mars... and then on the surface.

My first biography written in '73 was not 'Journey To The Moon.' It was 'Return To Earth.' Because for me, that was the more difficult task - disappointment.

A mind concerned about danger is a clouded mind. It's paralyzing.

I want people to go into space, to orbit around the world a few times, even to stay there for 24 hours and then come back to where they took off. And I also want people with a low income to be able to do that, not only rich people.

A hybrid human-robot mission to investigate an asteroid affords a realistic opportunity to demonstrate new technological capabilities for future deep-space travel and to test spacecraft for long-duration spaceflight.

I do celebrity ski races all over the world.

There's a need for accepting responsibility - for a person's life and making choices that are not just ones for immediate short-term comfort. You need to make an investment, and the investment is in health and education.

When we can demonstrate that we can take off horizontally and put something into orbit, then we can begin to talk about increasing the amount of payload. But to say, 'I'm going to do that and put people into orbit' is a real leap.

Whenever I gaze up at the moon, I feel like I'm on a time machine. I am back to that precious pinpoint of time, standing on the foreboding - yet beautiful - Sea of Tranquility. I could see our shining blue planet Earth poised in the darkness of space.

NASA needs to focus on the things that are really important and that we do not know how to do. The agency is a pioneering force, and that is where its competitive advantage lies.

We must still think of ourselves as pioneers to understand the importance of space.

I am definitely not rich.

Mars has been flown by, orbited, smacked into, radar inspected, and rocketed onto, as well as bounced upon, rolled over, shoveled, drilled into, baked, and even laser blasted.

I think there would be no shortage of applicants to the government astronaut corps to be settlers on the planet Mars. And I think this would be very inspiring.

Can you imagine, in 2030, taking a space cruise on the very ship that carried the first human beings to Mars? I can't believe that people wouldn't line up for that possibility.

For the future, primarily, we must educate people in science, engineering, technology and math.

I've led a life of such structured discipline and always had a goal in mind of knowing what I was doing, from West Point to the Air Force combat, MIT, looking for new things to study and get involved in. And then I got into the space program, and how disciplined can you get?

My favourite thing to do on this planet is to scuba dive.

I am Buzz Lightyear!

When President Kennedy took office, I was in the midst of my education.

Like actors and writers who are on and off again in terms of employment, I had a very unstructured life.

By refocusing our space program on Mars for America's future, we can restore the sense of wonder and adventure in space exploration that we knew in the summer of 1969. We won the moon race; now it's time for us to live and work on Mars, first on its moons and then on its surface.

Is the destiny of the human species to sit back and play with our mouse and computer and imagine, fantasize?

All the Chinese have to do is fly around the Moon and back, and they'll appear to have won the return to the Moon with humans. They could put one person on the surface of the Moon for one day and he'd be a national hero.

My Sunday mornings are spent in a recovery meeting in Pacific Palisades.

American greatness was elevated significantly after Sputnik.

My own American Dream was to serve my country as best I could and make a difference in America - and in the world.

I'm not in favor of just taking short-term isolated situations and depleting our resources to keep our climate just the way it is today.

Walking around on the moon was significantly easier than we'd thought it would be. There weren't any balance problems, so you weren't tumbling over.

Exploring and colonizing Mars can bring us new scientific understanding of climate change, of how planet-wide processes can make a warm and wet world into a barren landscape. By exploring and understanding Mars, we may gain key insights into the past and future of our own world.

Globalisation means many other countries are asserting themselves and trying to take over leadership. Please don't ask Americans to let others assume the leadership of human exploration. We can do wonderful science on the Moon, and wonderful commercial things. Then we can pack up and move on to Mars.

It was interesting to think that the very first liquid ever poured on the Moon, and the first food eaten there, were communion elements.

Instead of planning the retirement of the Space Shuttle program, America should be preparing the shuttles for their next step in space: evolving, not shutting them down and laying off thousands of people.

NASA's been one of the most successful public investments in motivating students to do well and achieve all they can achieve, and it's sad that we are turning the program in a direction where it will reduce the amount of motivation it provides to young people.

I was motivated to improve the U.S. strategy of going back to the moon in 1985. That's a long time ago. Going back to the moon would be a great achievement for tourism adventure flights.