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

I grew up in a country that I thought was special. And it was.

Ray Bradbury is one who is contributing to the understanding of the imagination and the curiosity of the human race.

The energy varies with the square of the velocity, so if you need five times the velocity, that's 25 times the energy.

Going to Mars would evolve humankind into a two-planet species.

I want to reach a new generation. That's why I am Twittering now. I have a BlackBerry, an iPhone and a Mac.

I've been to the Titanic in a yellow submarine and the North Pole in a Russian nuclear ice breaker.