M. E. Lehwalt

Ames Research Center

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Vance I. Oyama

Ames Research Center

B. J. Berdahl

Ames Research Center

F. Woeller

Ames Research Center

Herbert S. Ginoza

Ames Research Center

G. C. Carle

Ames Research Center

T. Wydeven

Lockheed Martin (United States)

E. V. Ballou

Ames Research Center

Peter C. Wood

Thunder Bay Regional Research Institute

R. Mack

Ames Research Center

Cooperative Institutions

Ames Research Center

National Aeronautics and Space Administration

San Jose State University

University of California San Francisco Medical Center

United States Department of the Army

Arthritis Treatment Center

Tel Aviv University

TRW Automotive (United States)

Lawrence Berkeley National Laboratory

University of California, Berkeley

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THE CHEMICAL ACTIVITIES OF THE VIKING BIOLOGY EXPERIMENTS AND THE ARGUMENTS FOR THE PRESENCE OF SUPEROXIDES, PEROXIDES, γ-Fe2O3 AND CARBON SUBOXIDE POLYMER IN THE MARTIAN SOIL

Life sciences and space research (1978)

Vance I. Oyama B. J. Berdahl F. Woeller M. E. Lehwalt

The evolution of N2, Ar, O2, and CO2 from Martian soil as a function of humidity in the Gas Exchange Experiment are correlated with the mean level of water vapor in the Martian atmosphere. All but O2 are associated with desorption. The evolution of oxygen is consistent with the presence of alkaline earth and alkali metal superoxides; and their peroxides and the gamma-Fe2O3 in the soil can account for the generation of radioactive gas in the Labeled Release Experiment. The slower evolution of CO2 from both the Gas Exchange Experiment and the Labeled Release Experiment are associated with the direct oxidation of organics by gamma-Fe2O3. The Pyrolytic Release Experiment's second peak may be carbon suboxide as demonstrated by laboratory experiments. A necessary condition is that the polymer exists in the Martian soil. We ascribe the activity of the surface samples to the reaction of Martian particulates with an anhydrous CO2 atmosphere activated by uv and ionizing radiations. The surface particles are ultimately altered by exposure to small but significant amounts of water at the sites. From the working model, we have predicted the peculiar nature of the chemical entities and demonstrated that the model is justified by laboratory data. The final confirmation of this model will entail a return to Mars, but the nature and implications of this chemistry for the Martian surface is predicted to reveal even more about Mars with further simulations in the laboratory.

Atmosphere of Mars

Martian soil

10.1016/b978-0-08-022022-2.50005-8

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Citations (27)

Thin-layer assay of chlorophyll and analogous dry-column separation with effluent fluorometry

Journal of Chromatography A (1974)

F. Woeller M. E. Lehwalt Vance I. Oyama

10.1016/s0021-9673(00)83176-3

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Biological effects of fuel and exhaust components from spacecraft descent engines employing hydrazine

M. E. Lehwalt F. Woeller Vance I. Oyama

The effect of the products of the Viking terminal descent engine fuel upon possible extraterrestrial life at the Martian landing site is examined. The effects of the engine exhaust, the hydrazine fuel, and the breakdown products of the latter on terrestrial microorganisms have been studied. The results indicate that the gaseous exhaust products would probably not be hazardous to microorganisms, but that liquid hydrazine would be lethal.

Hydrazine (antidepressant)

Descent (aeronautics)

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Implications of the hypohydrous history of Mars

Vance I. Oyama M. E. Lehwalt B. J. Berdahl

The extent to which fluvial processes occurred in Mars is considered with reference to the oxidation of soil organics by the gamma-Fe2O3/H2O2 system. Data from the Viking biology experiments suggest that the acidity of gamma-Fe2O3 controls the ionization of hydrogen peroxide - that is, in acid conditions and in the presence of large concentrations of formate, gamma-Fe2O3 reacts efficiently with peroxide to oxidize formate to CO2 and H2O. Fe3O4, alpha-Fe2O3, and calcite are basic and block the oxidation of formate. The properties of this system are consistent with the hypothesis that Mars has been under a severe regime of dryness.

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The search for life on Mars: Viking 1976 gas changes as indicators of biological activity

Origins of Life (1976)

Vance I. Oyama B. J. Berdahl G. C. Carle M. E. Lehwalt Herbert S. Ginoza

10.1007/bf00926949

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IMPLICATIONS OF THE HYPOHYDROUS HISTORY OF MARS

Life sciences and space research (1979)

Vance I. Oyama M. E. Lehwalt B. J. Berdahl

We have shown that clays, carbonates, α-Fe 2 O 3 , and Fe 3 O 4 . impart an alkaline state to aqueous solutions that govern the rate of decomposition of H 2 O 2 . In the presence of these materials singly, the production of 14 CO 2 from the oxidative decarboxylation process catalyzed by γ-Fe 2 O 3 is strongly inhibited. Because the results of the Viking Labeled Release Experiment were simulated exactly by the γ-Fe 2 O 3 /H 2 O 2 system, we conclude that these materials (clays, etc.) are not in such an abundance as to quench the peroxidase activity demonstrated on Mars. Because these materials are generally formed in an aqueous environment, we conclude that Mars has had a very long hypohydrous history.

10.1016/b978-0-08-023416-8.50010-6

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Chemical interpretation of Viking Lander 1 life detection experiment

Nature (1978)

E. V. Ballou Peter C. Wood T. Wydeven M. E. Lehwalt R. Mack

Atmosphere of Mars

Martian soil

Carbon fibers

10.1038/271644a0

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Citations (98)