I really hate to be put in the position of trying to justify something, a decision that was made. I'm a military guy: when a decision is made, I go along with it, whatever the manufactured controversy and criticism.

Astronauts are not superhuman. They lead ordinary lives and have varied personalities.

To appropriately respond to an emergency requires a very clear mind, to cooly analyze what the observations are and how to fix it.

Space tourism is a logical outgrowth of the adventure tourist market.

There's a tremendously satisfying freedom associated with weightlessness. It's challenging in the absence of traction or leverage, and it requires thoughtful readjustment. I found the experience of weightlessness to be one of the most fun and enjoyable, challenging and rewarding, experiences of spaceflight. Returning to Earth brings with it a great sense of heaviness, and a need for careful movement. In some ways it's not too different from returning from a rocking ocean ship.

Having walked on the Moon, I know something about what we need to explore, really explore, in space.

It's time to open the space frontier to citizen explorers.