Uncertainty Quantification in Planning for Potentially Hazardous Objects (PHOs) Mitigation

Planetary defense mitigation attempts require significant advanced mission planning and simulation of the mission.The simulation work is conducted using hydrodynamics codes and equation of state data (Barbee et al., 2018).The results of these pre-launch simulations are used in mission planning to predict targeting and timing requirements and to quantify the energy and delivery mechanism required to impart the necessary delta v to a specific object.The 2022 DART mission was a deliberate test of this process for mitigation by kinetic impact, beginning with hydrocode calibration and predictions (Stickle et al. 2020(Stickle et al. , 2022) ) and concluding with comparison to the impact experiment (Stickle et al., in press).Similar uncertainties exist for scenarios considering mitigation by stand-off nuclear burst, especially in scenarios where rendezvous into orbit around the target object is not possible.In these fastapproach scenarios, it may not be possible to predict the orientation of the target relative to the burst, and the distance from the burst to the target may have significant uncertainties arising from hardware capabilities and target positional uncertainty.Uncertainties on, e.g., the mass, shape, and material properties of the target may add further uncertainty to delta v predictions, but we have an incomplete understanding of their effects.Simulations of mitigation attempts currently reduce total simulation uncertainty by minimizing uncertainties in the energy imparted to the PHO, which places infeasible constraints on mission design.Here we explore the sensitivities of mitigation simulations to known uncertainties to establish feasible mission design constraints.