NASA and FEMA are working together to devise strategies in case a massive asteroid or comet is found heading toward the Earth. Although asteroids hit our planet on a regular basis, few cause significant damage. In 2013, a meteor exploded over the city of Chelyabinsk in Russia, injuring 1,100 people. Roughly 66 million years ago, an asteroid the size of Mount Everest hit the Earth, ending the age of dinosaurs. Researchers do not currently know of any asteroid or comet headed on a collision course with our planet.Read More Is Earth Ready for the Next Asteroid Strike?