[X] My Assistant

[marsbug]

I read this article on electrostatic transport of dust on the lunar surface a few days ago, and I was wondering if it had ever been discussed as an erosive or constructive force? What effect might it have had on lunar geology?

[dvandorn]

The reason I say that the Apollo experiment results (including LEAM, which was designed to look for dust particles) didn't get conclusive results in re electrostatic dust levitation is that we are just now seeing anything substantive published on the subject. It has taken a more advanced fields and particles understanding of the lunar environment than we had at the time to eliminate various other hypotheses and determine that the observed results were due to electrostatic levitation. Besides, the kinds of fields and energetic particles thought to be required for dust levitation weren't particularly evident in other experimental results, in particular the SIDE and CPLEE results. (The exhaust from the Apollo rocket engines, for example, had a much more noticeable impact on the lunar environment than did the terminator effects that cause the dust levitation.)

Again -- we simply don't see the kind of global dust cover on the tops of rocks, etc. that we would if dust levitation over eons had significant erosional or constructional effects. At least, IMHO. The dust deposited on the tops of rocks is well accounted for by the amount of dust and debris flung about by impact events, and in fact is very minor considering the great amounts of time these rocks have been lying on the surface.

I think the best comparison would be to say that electrostatic dust levitation has probably had the same erosional and constructional impact on lunar geology as the infall of myriad tons of meteoric dust per day on Earth has had on terrestrial geology. Yes, there is a very minor though observable effect, but its overall effect is by far overwhelmed by early orogenic and continuing impact processes.

-the other Doug