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Re: The Moon landing again - Fw: Neil Armstrong's Boots

From: Tom <tom@vondein.org>

>> This massive thrust would have blown the dust away from the landing area
>> creating a massive dust cloud, so why was thick dust still on the ground
>> and no massive dust cloud? Please explain NASA.

>No atmosphere, no blowing.    - Tom

I'd answer this somewhat differently.  The rocket jet would indeed dislodge the dust:  The particles
would acquire velocities, and would follow mostly-parabolic paths and eventually collide with and stay
on the surface again. While this might be labelled a "cloud", unlike in Earth's atmosphere these particles
 will presumably return to the Moon's surface in a few seconds, yet far away from the lunar lander.
 As to "why was thick dust still on the ground", most likely the dust was very thick.  
(many meters).

"The lunar surface is covered by a layer of unconsolidated debris called the lunar regolith (fig. 53). The thickness of the regolith varies from about 5 m on mare surfaces to about 10 m on highland surfaces. The bulk of the regolith is a fine gray soil with a density of about 1.5 g/cm3 , but the regolith also includes breccia and rock fragments from the local bedrock (reviews by Heiken et al. 1974 and Papike et al. 1982). About half the weight of a lunar soil is less than 60 to 80 microns in size. The grain size distribution is given in figure 55."

There may be an additional factor.  As I vaguely recall, there is an odd electrostatic attraction
 between the particles of lunar soil.  Perhaps not surprising, because except for subsurface
frozen-water deposits (and some polar craters) the moon is 'dry as a bone'.