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!

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.

There's no accepted global policy on what to do about asteroid impacts.

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.

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

We not only need to train people, we also need to develop deflection technologies.