Re: SPACE: Lunar Warfare

James Rogers (
Wed, 15 Jan 1997 16:31:02 -0800

At 11:22 PM 1/14/97 -0500, Michael Lorrey wrote:
>Also, the lunar terrain is much less conducive to shocks than earth
>terrain. What you are referring to is the whole structure of the moon
>being cool to the core, so it conducts sound throughout the moon, but
>not in the local scale as easily as earth does, as earth has a much
>higher moisture content (0% vs 40%) that greatly amplifies the effects
>of underground shock (any of you in SF know this from the damage in the
>Marina area during the quake as opposed to say, the top of Russian

Moisture content has a very significant impact on shock propagation.
Nuclear blasts in regions with a high water table exhibit shallower crater
depth, but a significantly larger shock damage radius. Water transmits
shock much better than either air or dry soil. However, this is mostly of
concern to underground structures since ground shock propagation is their
only significant threat other than overpressure. For most structures,
overpressure is the primary threat, not ground shock.

FYI, as a rule, conventional explosives have a 50% greater damage radius
underwater as they do in air due to differences in hydrostatic shock
propagation efficiency.

-James Rogers