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.

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

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.

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.

The frontier in space, embodied in the space colony, is one in which the interactions between humans and their environment is so much more sensitive and interactive and less tolerant of irresponsibility than it is on the whole surface of the Earth. We are going to learn how to relate to the Earth and our own natural environment here by looking seriously at space colony ecologies.

An asteroid can literally destroy 80 or 90 percent of the species that are alive on Earth. These are big events. I mean, this is called extinction.

Asteroids have hit the Earth millions of times. We can see them as shooting stars every night. When they get bigger, things get complicated. It is only a matter of time until a big one hits us. And since we can do something about it, we should.