The large population of 2r>100m near earth objects (NEOs) presents a certain hazard to life on earth. It has been proposed that a nuclear device may be used to alter the course of such objects, thereby averting a catastrophic collision with the earth. The asteroid interdiction problem includes a number of parameters. Many can potentially be determined by observation; these include size, composition, trajectory, center of mass, and required deflection velocity. However, the yield of the nuclear device necessary to provide sufficient impulse to the NEO to avoid a collision must be calculated. Two coupling parameters are needed for this: Ny, which gives the explosive yield deposited in the object as a fraction of the intercepted yield, and Nk, which gives a conversion efficiency between the energy deposited in the object and the total change in the object's kinetic energy. The Monte Carlo code TART in ussed to calculate Ny, and the radiation hydrodynamics code CALE is used to calculate Nk.