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.

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.

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.

For the first time in history, we have the chance to change the path of a celestial body. Let's realize what we're talking about here. We would be slightly changing the mechanics of our solar system to enhance our survival. That is gigantic!

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.

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.