Risk management applied to planetary defense

Increasing scientific evidence strongly supports the conclusion that the major extinctions in the history of life on Earth were caused by the impact of large near-Earth-orbit objects (NEOs) and that these impacts will continue. Although the annual likelihood of this threat from asteroids and comets is extremely low, the consequences are so disastrous they have no precedent in human history. Alternatives to the mitigation of this threat are vigorously debated and the author suggests the application of risk management to develop a consensus for the best strategy. An example of this methodology is applied to planetary defence. The conclusion is that present NEO detection programs should be intensified, NEOs should be characterized through rendezvous missions and that intercept systems studies should be undertaken. An education and public awareness initiative is also recommended.