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.

I understand that Detroit was a pretty rough place to grow up in the '70s and '80s.

Any observations from the Moon or a sense of realising this or that about the greater meaning of things wasn't as influential for me as the experience of coming back and dealing with being a person who's been to the Moon.

The life expectancy of people going to Mars may be decreased by the higher level of radiation that they receive.

I'm sure that there are places in the deserts in Australia that could be similar to where we might want to go on Mars.

Dwelling on an engine failure for a pilot as he rolls down the runway is NOT what he should be thinking about - it's obtaining a smooth liftoff! But in the back of his mind, he knows exactly what to do (or pretty much) and in many cases, if he's alone in the fighter aircraft, he has to leave that aircraft in an ejection seat in a big hurry!

Knowledge of the past and an optimistic view of the present give you great opportunities.