Possible Methane Sources on Mars Mona Houcheime 1,2 Dr. Richard Ulrich 1 1 Arkansas Center for Space and Planetary Sciences, University of Arkansas Fayetteville, AR 72701 2 Department of Biology, San Jose State University, San Jose, CA 95192 Detection of Methane led by three teams: Telescope CH 4 Abundance •Vladimir Krasnopolsky-- Catholic Univ. of America Canada-France-Hawaii Telescope 10 ± 3 ppbv •Michael Mumma--NASA/Goddard Space Flight Center CSHELL and Phoenix at Gemini South 10 to 30 ppbv •Vittorio Formisano--ESA/Mars Express Planetary Fourier Spectrometer 10 ± 5 ppbv Biotic CH 4 Source? Abiotic CH 4 Source? Future atmospheric and surface studies Localize methane emissions with high resolution spectrometers such as LIDAR Search for atmospheric/geologic indicators of weathering Determine isotopic ratio of atmospheric carbon (biotic origin low C 13 /C 12 ) Locate hydrothermal vents, hotspots methane hydrate/gas deposits Drilling investigations to test for presence of past or present life •Olivine hydration, in presence of CO 2 , is a kinetically and thermodynamically favored (in low- T, high P aqueous environments) reaction: CH 4 + 2H 2 O (+ weathered products) 4 •Presence and abundance of olivine (~30%) at the surface near equatorial regions is consistent with the current atmospheric conditions 3 . •Conditions support a cold and dry model of the early Martian surface that could have existed for a long time •Release of methane from hydrates (high P low T) within the Hydrate Stability Zone (HSZ) by geothermal heat 5 •Possible outgassing sources undetected with current spectroscopic instruments •Exogenous methane produced by impacts of comets, meteorites, and interplanetary dust (~6%) 1 References 1)Krasnopolsky, V. et al., Icarus , vol. 172, Issue 2, p. 537-54 December 2004 2)Formisano, V. et al., Science , vol. 306, p. 1758-1761, Decemb 3, 2004 3)Bibring, J.P et al., Science , vol. 307, p. 1576-1581, March 11 2005 4)Oze, C., Sharma, M., Geophysical Research Letters , vol. 32, L10203 (2005) 5)Max, M., Clifford, S., Journal of Geophysical Research , vol.105, no.E2, p.4165-4171, February 20, 2000 Methanogens oliv ine Thanks to the National Aeronautics and Space Administration for funding and supporting the Arkansas Space and Planetary Sciences Research for Undergraduates program. I would also like to thank Dr. Ulrich for his assistance. •Methane, predominantly produced by biological processes on Earth, is considered a biomarker on Mars •Current surface conditions (low T~ 200K, low P~ 6mbar, high UV exposure due to absence of ozone, presence of hydrogen peroxide) hostile to any life-forms on surface •Subpermafrost region is the most likely habitat of non-photosynthetic, anaerobic, respiring, methane-producing microorganisms •Only a small population would be needed to supply methane at a rate of 4g/sec •Metabolic substrates needed for growth of bacterial colonies are present:H 2 O, CO, CO 2 , H 2 1 •Presence of carbonates supports warm, wet model of early Mars •Methane-rich areas were detected in equatorial zones where water (and life-forms) may have existed 95% CO 2 (g) 10 ± 5ppb or 9.1x107 kg CH 4 (g) 2-5% Carbonates * Astro biology Art Gallery http://www.astrobio.net

Possible Methane Sources on Mars Mona Houcheime 1,2 Dr. Richard Ulrich 1 1 Arkansas Center for Space and Planetary Sciences, University of Arkansas Fayetteville,

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Possible Methane Sources on MarsMona Houcheime1,2 Dr. Richard Ulrich1

1Arkansas Center for Space and Planetary Sciences, University of Arkansas Fayetteville, AR 72701

2Department of Biology, San Jose State University, San Jose, CA 95192

Detection of Methane led by three teams: Telescope CH4 Abundance•Vladimir Krasnopolsky-- Catholic Univ. of America Canada-France-Hawaii Telescope 10 ± 3 ppbv•Michael Mumma--NASA/Goddard Space Flight Center CSHELL and Phoenix at Gemini South 10 to 30 ppbv•Vittorio Formisano--ESA/Mars Express Planetary Fourier Spectrometer 10 ± 5 ppbv

Biotic CH4 Source? Abiotic CH4 Source?

Future atmospheric and surface studiesLocalize methane emissions with high resolution spectrometers such as LIDARSearch for atmospheric/geologic indicators of weathering Determine isotopic ratio of atmospheric carbon (biotic origin low C13/C12) Locate hydrothermal vents, hotspots methane hydrate/gas depositsDrilling investigations to test for presence of past or present life

•Olivine hydration, in presence of CO2, is a kinetically and thermodynamically favored (in low-T, high P aqueous environments) reaction: CH4+ 2H2O (+ weathered products)4

•Presence and abundance of olivine (~30%) at the surface near equatorial regions is consistent with the current atmospheric conditions3. •Conditions support a cold and dry model of the early Martian surface that could have existed for a long time•Release of methane from hydrates (high P low T) within the Hydrate Stability Zone (HSZ) by geothermal heat5

•Possible outgassing sources undetected with current spectroscopic instruments •Exogenous methane produced by impacts of comets, meteorites, and interplanetary dust (~6%)1

References1)Krasnopolsky, V. et al., Icarus, vol. 172, Issue 2, p. 537-547, December 20042)Formisano, V. et al., Science, vol. 306, p. 1758-1761, December 3, 20043)Bibring, J.P et al., Science, vol. 307, p. 1576-1581, March 11, 20054)Oze, C., Sharma, M., Geophysical Research Letters, vol. 32, L10203 (2005)5)Max, M., Clifford, S., Journal of Geophysical Research, vol.105, no.E2, p.4165-

4171, February 20, 2000

Methanogens olivine

Thanks to the National Aeronautics and Space Administration for funding and supporting the Arkansas Space and Planetary Sciences Research for Undergraduates program. I would also like to thank Dr. Ulrich for his assistance.

•Methane, predominantly produced by biologicalprocesses on Earth, is considered a biomarkeron Mars•Current surface conditions (low T~ 200K,low P~ 6mbar, high UV exposure due to absenceof ozone, presence of hydrogen peroxide) hostileto any life-forms on surface•Subpermafrost region is the most likely habitatof non-photosynthetic, anaerobic, respiring,methane-producing microorganisms•Only a small population would be needed tosupply methane at a rate of 4g/sec•Metabolic substrates needed for growth of bacterial colonies are present:H2O, CO, CO2, H2

•Presence of carbonates supports warm, wetmodel of early Mars•Methane-rich areas were detected in equatorialzones where water (and life-forms) may haveexisted

95% CO2 (g)10 ± 5ppb or 9.1x107 kg CH4 (g)

2-5% Carbonates

* Astro biology Art Gallery http://www.astrobio.net

http://www.uark.edu/

http://www.nasa.gov/home/index.html

http://www.astrobio.net/news/modules.php?set_albumName=terraform&id=aco&op=modload&name=gallery&file=index&include=view_photo.php