An Overview of the Los Alamos Program on Asteroid Mitigation by a Nuclear Explosion

Abstract:

Los Alamos National Laboratory is standing up a new program to address the mitigation of a potentially hazardous objects (PHO) by using nuclear explosives. A series of efforts at Los Alamos have been working this problem for the last few years in an informal fashion. We now have a funded program to dedicate time to this important mission. The goal of our project is to study the effectiveness of using a nuclear explosive to mitigate (alter orbit or destroy) an PHO on an Earth crossing path. We are also pursuing studies of impact hazards should the international leadership decide not to organize a mission for active mitigation of a PHO. Such impact hazards are characterized as local, regional or global. Impact hazards include: a direct hit in an urban area (potentially catastrophic but highly unlikely); the generation a significant tsunami from an ocean impact close to a coastline and regional and global effects from medium to large impactors. Previous studies at Los Alamos have looked at 2D and 3D simulations in the deep ocean from large bolides, as well as impacts that have global consequences. More recent work has included radiation-hydrodynamic simulations of momentum transfer (and enhancement) from a low energy (10 kt) stand-off source, as well as surface and subsurface high energy explosions (100 kt - 10 Mt) for example PHOs. The current program will carefully look at two main aspects of using a standoff nuclear source: 1) a computational study for the optimum height-of-burst (HOB) of a stand-off burst using our best energy coupling techniques for both neutrons and x-rays; and 2) as a function of the nuclear energy produced and the HOB what is the optimum energy field: neutrons or x-rays. This team is also working with NNSA and NASA Goddard to compare numerical results for these complicated simulations on a well defined series of test problems involving both kinetic impactors and stand-off nuclear energy sources. Results will be shown by the co-authors on individual aspects of these simulations.