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

We could not wipe ourselves out with a nuclear war. I do not want so sound too positive. It would be a catastrophe, but it would not be a final one. We are not powerful enough for that. An asteroid could be that powerful. That is why we need to do our homework.

It is not enough to do a desktop exercise of a Beethoven symphony. You need to practice with an orchestra. The musicians need to read the notes. Otherwise it will be a disaster.

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.

This whole issue of limits to growth, which provides a psychological, as well as a physical, cap on potential expansion of activity and awareness, has had a very depressing effect on many people.... I don't for a moment think that there's any concept which anyone's working with now which will be followed as a straightforward scenario. But the idea embodied in concepts such as space colonization or space industrialization, or availability of nonterrestrial resources, is fundamental, and it will change the way in which people look at the future.

You almost wish you could turn off the COMM and just appreciate the deafening quiet.

We can both prevent asteroid impacts and address climate change. It's not either-or.