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Summary: ASTROBIOLOGY
Volume 6, Number 3, 2006
© Mary Ann Liebert, Inc.
Special Paper
Oxidant Enhancement in Martian Dust Devils and
Storms: Storm Electric Fields and Electron
Dissociative Attachment
GREGORY T. DELORY,1 WILLIAM M. FARRELL,2 SUSHIL K. ATREYA,3
NILTON O. RENNO,3 AH-SAN WONG,3 STEVEN A. CUMMER,4 DAVIS D. SENTMAN,5
JOHN R. MARSHALL,6 SCOT C.R. RAFKIN,7 and DAVID C. CATLING8,9
ABSTRACT
Laboratory studies, numerical simulations, and desert field tests indicate that aeolian dust
transport can generate atmospheric electricity via contact electrification or "triboelectricity."
In convective structures such as dust devils and dust storms, grain stratification leads to macro-
scopic charge separations and gives rise to an overall electric dipole moment in the aeolian
feature, similar in nature to the dipolar electric field generated in terrestrial thunderstorms.
Previous numerical simulations indicate that these storm electric fields on Mars can approach
the ambient breakdown field strength of 25 kV/m. In terrestrial dust phenomena, poten-
tials ranging from 20 to 160 kV/m have been directly measured. The large electrostatic fields
predicted in martian dust devils and storms can energize electrons in the low pressure mar-
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