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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: Implications for Life and Habitability
SUSHIL K. ATREYA,1 AH-SAN WONG,1 NILTON O. RENNO,1 WILLIAM M. FARRELL,2
GREGORY T. DELORY,3 DAVIS D. SENTMAN,4 STEVEN A. CUMMER,5
JOHN R. MARSHALL,6 SCOT C.R. RAFKIN,7 and DAVID C. CATLING8,9
ABSTRACT
We investigate a new mechanism for producing oxidants, especially hydrogen peroxide
(H2O2), on Mars. Large-scale electrostatic fields generated by charged sand and dust in the
martian dust devils and storms, as well as during normal saltation, can induce chemical
changes near and above the surface of Mars. The most dramatic effect is found in the pro-
duction of H2O2 whose atmospheric abundance in the "vapor" phase can exceed 200 times
that produced by photochemistry alone. With large electric fields, H2O2 abundance gets large
enough for condensation to occur, followed by precipitation out of the atmosphere. Large
quantities of H2O2 would then be adsorbed into the regolith, either as solid H2O2 "dust" or
as re-evaporated vapor if the solid does not survive as it diffuses from its production region
close to the surface. We suggest that this H2O2, or another superoxide processed from it in
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