The universe does not behave according to our pre-conceived ideas. It continues to surprise us.

"Sooner or later disasters such as an asteroid collision or a nuclear war could wipe us all out, But once we spread out into space and establish independent colonies, our future should be safe."

The downside of my celebrity is that I cannot go anywhere in the world without being recognized. It is not enough for me to wear dark sunglasses and a wig. The wheelchair gives me away.

We explore because we are human and we want to know. I hope that Pluto will help us on that journey.

To confine our attention to terrestrial matters would be to limit the human spirit.

It is generally recognised that women are better than men at languages, personal relations and multi-tasking, but less good at map-reading and spatial awareness. It is therefore not unreasonable to suppose that women might be less good at mathematics and physics.

You can't regulate every lab in the world.