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View Full Version : Mars Methane Mystery Still Beckons



Fraser
2008-Nov-03, 10:30 PM
We've known about the methane in Mars' atmosphere for over four years now. But we don't know where it is coming from. On Earth, methane is produced from biological agents: rotting vegetation or flatulence from large animals like cows. But, of course, with our extensive explorations of Mars with rovers and high-resolution [...]

More... (http://www.universetoday.com/2008/11/03/mars-methane-mystery-still-beckons/)

John Jaksich
2008-Nov-16, 01:47 AM
The mass spectrogram from the original Viking missions provided some clues as to what is actually in the atmosphere of Mars...though rather crudely...in the classic text by Professors McLafferty and Turicek---is listed a reproduction of Viking II mass spectrum of the Martian atmosphere...Methane is a background component with the atomic masses of 17, 16, 15, 14, 13, & 12 -- with the 16 and 12 peaks as the most abundant peaks---followed by 17 and 14...there are many more peaks in the spectrum but I don't have the means to reproduce them here nor the copyrighted permissions. The most abundant peak is at a mass of 37... the spectrum was produced on sol 5/6 ( 1976 I presume ).

JonClarke
2008-Nov-16, 06:01 AM
Actually the Viking data was rather good. It did not have the sensitivity required for methane detection, which requires ppb level sensitivity.

John Jaksich
2008-Nov-16, 06:37 AM
As in all NASA endeavors the budgetary ax falls in a fashion that is somewhat haphazard. I am unaware if there was a chromatography experiment on board Viking--to begin with---but looking at trace of the M/S it is apparent in hindsight that there was Methane on Mars at that time. In terms of signal-to-noise --it took an "averaged-out" -- three background scans for Viking II to discern any presence of organic molecules. Given what we know now about Mars...maybe we "lucked-out" since current studies suggest that the distribution of simple organic gases is not isotropic throughout the Martian "atmosphere".

The text that I am quoting the M/S finding is the following:

Interpretation of Mass Spectra
4th edition
Fred W. McLafferty
Frantisek Turecek

University Science Books
Sausalito CA
1993

ISBN 0935702253