« Steve Squyres rocks | Main | The Elysium Sea? »


Rick Sterling

I have a question about Carol Stoker's 36 Annual Lunar & Planetary Conference abstract("Characterization Of A Subsurface Biosphere In A Massive Sulfide Deposit At Rio Tinto, Spain:Implications For Extant Life On Mars"). In her abstract, Carol Stoker states, " A similiar subsurface chemoautotrophic biosphere could be living on Mars today and producing methane that, when released to the atmosphere, could potentially be a source for the methane that has been observed in the Martian atmosphere by the Mars Express mission." Secondly, NASA has stated regarding her Rio Tinto research, "The work by the scientists mentioned in the reports cannot be used to directly infer anything about life on Mars, but may help formulate the strategy for how to search for Martian life." I can't understand how Carol's abstract & NASA's statement can both be correct. It seems to me(as even the title of Carol Stoker's abstract states) that her work can be used to infer something about life on Mars. Am I misreading Carol's abstract? Bruce or someone else please help me out with my confusion! Finally, one other question. Will a finding of subsurface liquid water in the Martian Methane areas by the Mars Express MARSIS instrument shift Carol Stoker's mars life finding's from possible to probable?

Bruce Moomaw

Well, wht her statement at the Bad Astronomy site says is simply that she was speculating that the methane MIGHT be produced by subsurface methanogenic bacteria, and that her studies at Rio Tinto seem to confirm that this is a real possibility.

But a correlation between methane and subsurface liquid water, while interesting, wouldn't really do that much to ACTIVELY bolster the case for Martian life -- because two of the leading nonbiological theories for the methane involve it either being directly emitted by volcanic vents (which would also thaw the large amount of local subsurface ice in Mars' "cryosphere") or being released from subsurface methane clathrates thawed by local geothermal heat (same side effect). This phenomenon is very much worth investigating, and if we do find signs of liquid water in the high-CH4 regions it will further bolster the case for getting down there onto the surface fast and studying the place in-situ -- but, by itself, a methane/liquid H2O correlation just indicates a promising possible dwelling place for life, not further direct evidence that the methane is being biologically produced.

Rick Sterling

Formaldehyde claim inflames Martian debate. V. Formisano also reports discovery of HF & HBr in Martian atmosphere. http://www.nature.com/news/2005/050221/full/050221-15.html

Rick Sterling

German Experiments Validating Formisano Mars Methane-Formaldehyde Link. http://aviationnow.ecnext.com/free-scripts/comsite2.pl?page=aw_document&article=03145p09


Mahlzeit ihr 2,ich hoffe ihr habt noch viel Spass in der großen weetin Welt. Was war denn das abgefahrenste was ihr bisher gegessen habt (Hund/Katze/Maus)? Oder geht eure kulinarische Neugier nicht so weit?GrüßeNiko

The comments to this entry are closed.