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| Titel |
Lunar Dust Experiment (LDEX): First Results |
| VerfasserIn |
Mihaly Horanyi, Sam Gagnard, David Gathright, Eberhard Gruen, David James, Sascha Kempf, Mark Lankton, Ralf Srama, Zoltan Sternovsky, Jamey Szalay |
| Konferenz |
EGU General Assembly 2014
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 16 (2014) |
| Datensatznummer |
250090516
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| Publikation (Nr.) |
 EGU/EGU2014-4757.pdf |
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| Zusammenfassung |
| The lunar dust environment is expected to be dominated by submicron-sized dust particles
released from the Moon due to the continual bombardment by micrometeoroids, and possibly
due to UV radiation and plasma-induced near-surface intense electric fields. The Lunar Dust
EXperiment (LDEX) instrument is designed to map the spatial and temporal variability of
the dust size and density distributions in the lunar environment onboard the Lunar
Atmosphere and Dust Environment Explorer (LADEE) mission [1, 2] orbiting the Moon
since 10/6/2013. LDEX is an impact detector, capable of reliably detecting and
measuring the mass of submicron and micron sized dust grains. LDEX also measures the
collective currents from low-energy ions and from the impacts of dust grains that
are below the detection threshold for single dust impacts; hence it can search for
the putative population of grains with radii ~ 0.1 μm lofted over the terminator
regions by plasma effects. This talk will summarize the preliminary analysis of the
observations to date: 1) LDEX identified the dust ejecta cloud that is maintained by
micrometeoroid bombardment. As predicted, the density of the dust ejecta cloud rapidly
increases toward the surface, and it also shows strong temporal variability, most likely
related to the stochastic nature of the meteoroid impacts. 2) LDEX, as of yet, has not
confirmed the existence of levitated dust clouds. This puts strict new upper limits on the
density of small lofted grains, especially during periods of low ion fluxes entering the
instrument.
[1] Elphic et al., Proc. Lunar. Sci. Conf. 44th, 1719 (2013)
[2] Horanyi et al., Proc. Lunar. Sci. Conf. 43th, 1659 (2012). |
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