When I am getting ready to cross a street, I look both ways before crossing. My bones, my muscles, are not what they used to be, so I am careful when I go up and down stairs, because I've heard stories of older people falling and having very disabling injuries. I have enough things that begin to go a little bit wrong as I get a little bit older.

To send humans back to the moon would not be advancing. It would be more than 50 years after the first moon landing when we got there, and we'd probably be welcomed by the Chinese. But we should return to the moon without astronauts and build, with robots, an international lunar base, so that we know how to build a base on Mars robotically.

Certainly, I've never wanted to live on past achievements.

We can continue to try and clean up the gutters all over the world and spend all of our resources looking at just the dirty spots and trying to make them clean. Or we can lift our eyes up and look into the skies and move forward in an evolutionary way.

I think humans will reach Mars, and I would like to see it happen in my lifetime.

I'm in favor of changing the destination of humans. There are a lot of manned missions that can be done, but not in the direction of the moon.

A family needs to work as a team, supporting each other's individual aims and aspirations.