In the early days of the solar system asteroid impacts were much more common than they are today. While the planets were still forming there were plenty of planetary construction materials still orbiting the sun, searching for a home. The planets, the moons, and all that excess debris orbited the sun like so many cars whipping around a great cosmic roundabout….

Check out the original article: [Slashgear]Asteroids And Earth’s Fate: Are We Really Prepared To Prevent A Catastrophe?