Deflection Driven Evolution of Asteroid Impact Risk Under Large Uncertainties

The threat of asteroid impacts on the Earth can be mitigated through de- ection missions. The de ection capability has previously been omitted in asteroid impact risk analysis work that quanties impact damage on the Earth. Here we investigate the eect of pre-designed de ection missions on the risk prole of the ctitious impact scenario 2019 PDC. The impact risk analysis is based on a statistical approach. We sample orbital and physical property distributions that provide a complete representation of possible impact scenarios. Three pre-designed kinetic impactor de ection missions are considered in separate simulations. The de ection mission imposes a de ection V on the asteroid and the impulse enhancement factor is cal- culated as part of the analysis. The post-de ection impact risk is compared to the unde ected risk situation. Variations in physical and orbital proper- ties make the outcome of de ection missions uncertain. It can therefore be inadequate to label de ection mission outcomes in binary terms of success and failure. Instead, dening a satisfactory risk reduction goal and scal- ing the de ection mission capability to deliver this risk reduction is more accurate. In addition, the results highlight dilemmas that decision-makers would face in an asteroid threat scenario. By implementing a de ection mission, the potential impact point of the asteroid is moved, threatening new populations and potentially increasing damage in case of an impact.