Initiating a nuclear explosive device above, on, or slightly beneath, the surface of a threatening celestial body is a potential deflection option, with the optimal detonation height dependent upon the composition and size of the object.Solem, J. C. (1995). "Interception and disruption", in Proceedings of Planetary Defense Workshop, Livermore, CA, May 22–26, 1995, CONF-9505266 (LLNL, Livermore, CA), pp. 219–228 (236–246). It does not require the entire NEO to be vaporized to mitigate an impact threat. In the case of an inbound threat from a "rubble pile", the stand off, or detonation height above the surface configuration, has been put forth as a means to prevent the potential fracturing of the rubble pile. The energetic neutrons and soft X-rays released by the detonation, which do not appreciably penetrate matter, are converted into heat upon encountering the object's surface matter, ablatively vaporizing all line of sight exposed surface areas of the object to a shallow depth, turning the surface material it heats up into ejecta, and, analogous to the ejecta from a chemical rocket engine exhaust, changing the velocity, or "nudging", the object off course by the reaction, following Newton's third law, with ejecta going one way and the object being propelled in the other. Depending on the energy of the explosive device, the resulting rocket exhaust effect, created by the high velocity of the asteroid's vaporized mass ejecta, coupled with the object's small reduction in mass, would produce enough of a change in the object's orbit to make it miss the Earth.
initiating a nuclear explosive device above on or slightly beneath the surface of a threatening celestial body is a potential deflection option with the optimal detonation height dependent upon the composition and size of the objectsolem j c (1995) "interception and disruption" in proceedings of planetary defense workshop livermore ca may 22–26 1995 conf-9505266 (llnl livermore ca) pp 219–228 (236–246) it does not require the entire neo to be vaporized to mitigate an impact threat in the case of an inbound threat from a "rubble pile" the stand off or detonation height above the surface configuration has been put forth as a means to prevent the potential fracturing of the rubble pile the energetic neutrons and soft x-rays released by the detonation which do not appreciably penetrate matter are converted into heat upon encountering the object's surface matter ablatively vaporizing all line of sight exposed surface areas of the object to a shallow depth turning the surface material it heats up into ejecta and analogous to the ejecta from a chemical rocket engine exhaust changing the velocity or "nudging" the object off course by the reaction following newton's third law with ejecta going one way and the object being propelled in the other depending on the energy of the explosive device the resulting rocket exhaust effect created by the high velocity of the asteroid's vaporized mass ejecta coupled with the object's small reduction in mass would produce enough of a change in the object's orbit to make it miss the earth