How would we stop a killer asteroid?

Sixty-five million years ago, an asteroid killed off the dinosaurs. So how can we can we humans stop an asteroid from wiping us out, too?

According to NASA, over 100 tons of cosmic dust hit our planet every day, disintegrating into our atmosphere.

Car-sized asteroids hit our planet about once a year, creating huge fireballs that burn up long before hitting the surface of the planet.

But once every few million years, an object large enough to threaten civilization hurtles towards earth. Fortunately, NASA has a few plans to stop any potential Armageddon.

To find out more, check out the above episode of "Space, Down to Earth!"