Every couple of years, the earth is hit by a body with energy near that of the Hiroshima bomb. Deposited high in the atmosphere these events causes little or no damage. On longer timescales, impacts occur with the potential to destroy regions, or whole civilizations. Learn about the impact threat, followed by a systematic development of the requirements to divert such an object. Series: "Lawrence Livermore National Lab Science on Saturday" [Science] [Show ID: 17643]