Boslough and Crawford [Mark Boslough and David Crawford of the Sandia National Laboratories in New Mexico] ran repeated simulations of the Tunguska event [for an rticle forthcoming in the International Journal of Impact Engineering], trying to reproduce the scale of the devastation seen in the region. From this they concluded that even if the airburst explosion took place at an altitude of 12 kilometers or higher, it probably had a magnitude of only 3 to 5 megatons. This is considerable less than the popular figure of 10 to 15 megatons, and less than 1% the high end suggestion of 700 megatons. That such a comparatively small explosion could cause this much damage is due to the fact that it was not a point explosion at the airburst altitude that caused the damage, but the fireball and shockwave that continued moving towards the surface. At a height of around 4 kilometers, the simulations show, the fireball came to a stop, but the shockwave continued on. It was the shockwave, not the explosion at the airburst altitude and not even the streaking fireball, which was responsible for most of the devastation in the forest.
"The Tunguska Riddle: How Powerful was the Greatest Asteroid Impact in Recorded History?"
Amir Alexander
The Planetary Society
15 April 2008
Link: Article from The Planetary Society
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Other previous article by Mark Boslough on impact assessment and modeling (from the International Journal of Impact Engineering).
Axial focusing of energy from a hypervelocity impact on earth
International Journal of Impact Engineering, Volume 17, Issues 1-3, 1995, Pages 99-108
M. B. Boslough, E. P. Chael, T. G. Trucano, D. A. Crawford
The impact of periodic comet shoemaker-levy 9 on jupiter
International Journal of Impact Engineering, Volume 17, Issues 1-3, 1995, Pages 253-262
D. A. Crawford, M. B. Boslough, T. G. Trucano, A. C. Robinson
Dynamical properties measurements for asteroid, comet and meteorite material applicable to impact modeling and mitigation calculations
International Journal of Impact Engineering, Volume 17, Issues 1-3, 1995, Pages 341-352
M. D. Furnish, M. B. Boslough, G. T. Gray III, J. L. Remo
Hypervelocity testing of advanced shielding concepts for spacecraft against impacts to 10 km/s
International Journal of Impact Engineering, Volume 14, Issues 1-4, 1993, Pages 95-106
M. B. Boslough, J. A. Ang, L. C. Chhabildas, W. D. Reinhart, C. A. Hall, B. G. Cour-Palais, E. L. Christiansen, J. L. Crews
Shock-induced solid-state chemical reactivity studies using time-resolved radiation pyrometry
International Journal of Impact Engineering, Volume 5, Issues 1-4, 1987, Pages 173-180
M. B. Boslough
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