Hi James

There is pretty good evidence that the die-out of dinosaurs resulted from an ASTEROID (not comet) impacting Earth near the Yucatan Pennisula of Mexico.

There is some very,very, very small chance that a bigger asteroid could someday destroy Earth. NASA has been tasked with watching the sky for such asteroids and determining their orbit. If we find them soon enough, maybe we can send a spaceship out there to deflect the asteroid so it wouldn't hit Earth. So our nation is aware of this potential disaster and working on it!

Paulett