Anytime we can save lives or prevent the destruction of property, we should do it.

You see the Earth as a bright blue and white Christmas tree ornament in the black sky. It's so small and so fragile - you realize that on that small spot is everything that means everything to you; all of history and art and death and birth and love.

If we do our homework right, never again should an asteroid that can do damage on the ground impact the Earth. We're living in a time-with our technology-we have the capability to eliminate that major shaper of evolution . . . the evolution of life on this planet.

Anytime we can save lives or prevent the destruction of property, we should do it.

It would take an extremely large spacecraft to deflect a large asteroid that would be headed directly for the Earth.

In the short term, some deadly virus might be more important, but in the long run there is hardly anything more important than asteroids.

We need early warning systems, technologies to deflect an asteroid - and we need political preparedness as well. It needs to be clear who is to decide what, who launches the rockets, who presents which bills to its citizens. This is a planetary decision. We need to do this all together. Or it will not happen.