Degradation of Organics Due to Glow Discharges Under Simulated Martian Conditions
- Paper number
IAC-06-A3.P.3.16
- Author
Dr. Carlos Calle, National Aeronautics and Space Administration (NASA)/Kennedy Space Center, United States
- Coauthor
Dr. Charles Buhler, United States
- Coauthor
Dr. Paul Hintze, National Aeronautics and Space Administration (NASA)/Kennedy Space Center, United States
- Coauthor
Dr. Luz Marina Calle, National Aeronautics and Space Administration (NASA)/Kennedy Space Center, United States
- Coauthor
Dr. Steve Trigwell, United States
- Coauthor
Dr. Andrew Schuerger, University of Florida, United States
- Year
2006
- Abstract
The unexpected and striking discovery of the complete lack of organic materials found by the two Viking lander missions to Mars has been tentatively explained as being due to glow discharges in the Martian atmosphere. Preliminary tests performed by Oyama and Berdahl [1] in which rock fragments were tumbled at a wide range of atmospheric pressures for individual constituents of the Martian atmosphere showed glow discharge emission toward the blue region of the spectrum. Minimum electron energies of 450 eV were sufficient to generate sustained plasmas. From those studies, the authors found it plausible to ascribe triboelectric discharges between particles during recurring dust storms and dust devils to account for the production of both oxidized and reduced species such as atomic oxygen and carbon suboxide. Oyama and Berdahl believed that the hypothesis should be verified experimentally, but these experiments had not been carried out until now. In this paper, we report on our recent efforts to expose organics to glow discharges produced by the rapid discharge of electrostatic energy stored in individual Martian stimulant dust particles at simulated Martian atmospheric conditions. In a recent paper [2],we have reported on our experimental measurements of organic degradation on Martian stimulant dust grains when exposed to artificial glow discharge plasmas generated with electric fields of 300 kV/m from metal electrodes. The work that we report here describes our method of generating glow discharges directly from dust particles electrostatically charged by mutual collisions, a process akin to what may happen on Mars. An apparatus was constructed to reproduce the electrostatic charging effect of dust particles interacting during the frequent Martian dust devils. Measurements of glow discharge from the particles charged by mutual contact were obtained. Known organics were introduced to the particles prior to the experiments. Simulated dust devils under atmospheric conditions similar to those of Mars were produced to electrostatically charge these organic-laden particles. Gas chromatograph-Mass spectrometer analyses were done on particles sampled from three different locations. Our results are consistent with organic degradation of the beads after exposure to electrostatic glow discharges from the colliding grains. [1] Oyama, V.I. and B.J. Berdahl, “The Viking gas exchange experiment results from Chryse and Utopia surface samples,” JGR, 82, pp. 4669-4676 (1977) [2] Hintze, P.E., C.R. Buhler, L.M. Calle, C.I. Calle, S. Trigwell, J.W. Starnes, and A.C. Shuerger, “Degradation of organics in a glow discharge under Martian conditions,” LPS XXXVII, 2098 (2006)
- Abstract document
- Manuscript document
IAC-06-A3.P.3.16.pdf (🔒 authorized access only).
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