Hypervelocity Nuclear Interceptors for Asteroid Deection or Disruption

An intercept mission with nuclear explosives is the only practical mitigation option against the most probable impact threat of near-Earth objects (NEOs) with a short warning time (e.g., much less than 10 years). Although a less destructive, standoff nuclear explosion can be employed in such a last minute intercept mission, the momentum/energy transfer created by a shallow subsurface nuclear explosion is at least 100 times larger than that of a standoff nuclear explosion. However, the existing penetrated subsurface nuclear explosion technology limits the impact velocity to less than approximately 300 m/s because higher impact velocities destroy prematurely the detonation fusing devices. Also, a precision standoff explosion at an optimal height of burst above an irregularly shaped, smaller NEO is a technically challenging task, especially for intercept velocities of 2 to 30 km/s. Therefore, signicant advances in hypervelocity nuclear interceptor technology needs to be achieved soon to enable a last minute nuclear deection/disruption mission with intercept velocities as high as 30 km/s. This white paper briey describes the current as well as planned research activities at the Iowa State Asteroid Deection Research Center for developing such game changing space technology for mitigating the most probable impact threat of smaller NEOs with a short warning time.