The Lunar Surface: A Dusty Plasma Laboratory
Mihaly Horanyi
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Laboratory for Atmospheric and Space Physics (LASP)
Department of Physics
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Date and time:Ìý
Friday, February 8, 2013 - 1:00pm
Abstract:Ìý
The ÃÛÌÇÖ±²¥ Center for Lunar Dust and Atmospheric Studies (CCLDAS) is focused on experimental and theoretical investigations of the lunar surface, including dusty plasma and impact processes, the origins of the lunar atmosphere, and the development of new instrument concepts, with a complementary program of education and community development. This talk will discuss on our science results.
The lunar surface is exposed to a variety of plasma conditions as a function of local time, solar activity, and orbital position. The variable exposure to solar wind, UV radiation, magnetospheric plasmas, and meteoroid impacts result in a complex, time-dependent environment, which creates a natural dusty plasma laboratory. The charging, possible subsequent mobilization, and transport of fine lunar dust have remained a controversial issue since the Apollo era, and have been suggested to lead to the formation of a ‘dusty exosphere’, extending tens to hundreds of kilometers above the surface. CCLDAS is conducting a newly-conceived series of laboratory experiments supplemented by state-of-the-art theory and modeling, to determine: (1) The properties of a carefully-simulated near-surface plasma environment, and the intense localized electric fields and potentials expected to develop due to differential charging near the terminator regions and in shadows cast by topographic features. (2) The charging of grains resting on dusty surfaces and stirred by activities, their possible mobilization, lift-off, transport and adhesion. (3) The microphysics of impact phenomena from hypervelocity micrometeoroids and their interaction with the lunar environment.
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