mumma_ Detection and mapping of Methane and Water on Mars: Evidence for intense local enhancements in Methane. Michael J. Mumma Goddard Center for Astrobiology NASA GSFC Robert A. Novak (Iona College) Michael A. DiSanti (NASA GSFC) Boncho P. Bonev (Univ. of Toledo at GSFC) Neil Dello Russo (CUA at GSFC) Tilak Hewagama (Univ. of Maryland at GSFC Michael Smith (NASA GSFC)
Why is Earth WET ? (and ALIVE?) mumma_
Mars was WET - Was it also alive? Is it now alive? HST: Mars in 1995 mumma_
mjm_ Long-slit mapping of Methane and Water on Mars
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mjm_ Methane and Water on Mars Klassen et al. Icarus 138:36-48 (1999)
Methane and Water on Mars UT 20.8 March 2003 (L s = 155 o) S.E. lat = -7.4 o, long = o 7.0 arc-sec diameter NASA/IRTF CSHELL 0.5 arc-sec slit WFPC2 Image: 1 May 1999 (L s = 132 o ) S.E. lat = +19 o, long = 285 o STSCI-PRC99-27D (Bell, Wolff, et al.) mjm_
CSHELL slit position 20 March 2003 H 2 O -- | |-- CH 4 R1 | Methane and Water on Mars mjm_ Wavenumber, cm -1
Methane and Water on Mars UT 8.4 May 2003 L s = 181 o S.E. lat = 17.5 o S, long = o W 10.0 arc-sec diameter Image: UT 9.24 May 2003 S.E. long = 42 o W ACS J. Bell and M. Wolff Sub-solar point mjm_ Gemini South/Phoenix 0.17 arc-sec slit
CH | |---- H 2 O --- | | | | R1 R0 mjm_ Methane and Water on Mars Gemini-South/Phoenix 8 May 2003 L s = 181 o : CML o W Difference spectrum: 25º N - 18º S slit position
mjm_ Methane on Mars: Gemini-South/Phoenix 8 May 2003 CML o W Wavenumber, cm -1
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mjm_ Methane and Water on Mars
mjm_ Methane and Water on Mars
mjm_ Methane and Water on Mars
mjm_ Methane and Water on Mars CML 304 o
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mjm_ Methane and Water on Mars CH 4 on Mars : Present work; Formisano et al. (PFS); Krasnopolsky et al. (CFHT); Its presence requires ongoing recent release (300 yr photochemical lifetime). This Work: Two CH 4 spectral lines (R0, R1) are detected. Quantitative abundances agree. Quiescent levels range from 20 ppb to 60 ppb (at high latitudes). Two regions of major enhancement are found: 250 ppb and (up to) 800 ppb. Discrete source regions are needed. The production/release mechanism is related to temperature. A more-efficient destruction mechanism may be implied (gas-grain chemistry?) Possible abiotic origins of locally released methane: Geothermal activity (ala serpentization on Earth) - no supporting evidence. Test by C x. Release of methane hydrate (from juvenile Mars?) - why now? Test by D/H ratio. Possible biotic origin of locally released methane: Methanogens? - test by 13 C/ 12 C ratio in CH 4 ; higher order organics. Release of methane hydrate (from deep biosphere?) - Test by D/H ratio. Next steps: Firm up spatial variations - analyze additional maps, acquire additional data. Examine dependence on season, temperature, correlation with water, etc. Conduct in situ studies: orbital (e.g., MARVEL, OOO-2), airplane (e.g., ARES), landers.
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mjm_ Methane and Water on Mars
mjm_ Methane and Water on Mars
mjm_ Methane and Water on Mars