Our planet has been continually bombarded by asteroids since its formation, 4.5 billion years ago. While the frequency of large impacts has decreased, many potential Near-Earth Object threats remain undiscovered, so if or when they will impact Earth remains unknown. Fortunately, if an Earth-threatening asteroid is discovered in time, there are ways to mitigate or even prevent a disaster. Scientists at LLNL provide computer simulations in preparation these scenarios so if the time comes where an asteroid is headed our way, we will be prepared. Series: "Lawrence Livermore National Lab Science on Saturday" [Science] [Show ID: 35698]