It's very dangerous to put astronauts on a moon base where there's radiation, solar flares and micro meteorites. It'd be much better to put robots on the moon and have them mentally connected to astronauts on the Earth.

We have the media, which is such a waste in the sense that you can actually feel your IQ get lower as you watch TV.

I am a figure skater, which helps me appreciate Newton's theory of mechanics.

Sooner or later, we will face a catastrophic threat from space. Of all the possible threats, only a gigantic asteroid hit can destroy the entire planet. If we prepare now, we better our odds of survival. The dinosaurs never knew what hit them.

In science, nothing is ever 100% proven.

Our grandkids will lead the lives of the gods of mythology. Zeus could think and move objects around. We'll have that power. Venus had a perfect, timeless body. We'll have that, too. Pegasus was a flying horse. We'll be able to modify life in the future.

So often, science fiction helps to get young people interested in science. That's why I don't mind talking about science fiction. It has a real role to play: to seize the imagination.