MSL - SAM and CHEMIN, Discussion of the science/results from these instruments |
MSL - SAM and CHEMIN, Discussion of the science/results from these instruments |
Nov 12 2019, 07:10 PM
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#241
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Newbie Group: Members Posts: 13 Joined: 19-December 04 Member No.: 125 |
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Nov 14 2019, 03:49 AM
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#242
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Member Group: Members Posts: 507 Joined: 10-September 08 Member No.: 4338 |
Quantitatively, the relative increase in spring and summer of oxygen seems to be roughly double the increase of methane (from eyeballing the diagram). Then in fall and winter the changes are reversed. This seems consistent with a CO2 + 2H2O --> CH4 + 2O2 atmospheric reaction that can be reversed. Although a straight H2O dissociation has been ruled out, perhaps there is some condition or catalyst that promotes the interaction of the two gasses. The paper mentions the possibility of a soil release but then a particular quantitative correlation would seem coincidental. It might be interesting to see if there is any correlation with deviations from predicted atmospheric water vapour. |
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Nov 14 2019, 10:46 PM
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#243
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Senior Member Group: Members Posts: 1057 Joined: 17-February 09 Member No.: 4605 |
There does seem to be a tentative correlation between the observed oxygen mixing ratio and the annual variation in both atmospheric pressure and water content. The thing that caught my eye is the data points in winter dropping well below predictions, but consistent with the atmospheric pressure during southern ice cap winters being lower than for northern winters. Gale has already thrown a few surprises and the conundrum for those struggling to develop hypotheses is the inability to determine whether the variations are global or a feature of Gale or perhaps craters in general.
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Jan 1 2020, 12:57 AM
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#244
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Member Group: Members Posts: 507 Joined: 10-September 08 Member No.: 4338 |
https://agupubs.onlinelibrary.wiley.com/doi...29/2019GL083800
https://www.space.com/mars-methane-mystery-...nswer-soon.html Day/Night variation in methane investigated. |
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Feb 23 2021, 10:17 AM
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#245
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Junior Member Group: Members Posts: 94 Joined: 11-August 12 Member No.: 6536 |
So I was looking through the upcoming LPSC abstracts and found these. In Glenn Torridon they finally got away from the perchlorates that had caused so much trouble and they did a bunch of wet chemistry experiments including the first one using a new reagent called TMAH. The experiments went well however they still don't know what the Martian organics are. They are thermally unstable and decompose to CO2 when heated. The wet chemistry was supposed to find a way around that by creating more stable derivatives which would survive the heating process. However the results are still messy and they still have problems with internal contamination within SAM. They see evidence of sulfur containing organics, some of which are six membered rings called aromatics. Another theory is that the Martian organics are organic salts like oxalates.
Abundance of carbon seems to be around 1 part per thousand, with as much as 1% by weight in some of the sand dunes. LPSC SAM results including wet chemistry LPSC abstract : SAM wet chemistry using TMAH for the first time LPSC abstract: Organic salts? |
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Jan 18 2022, 09:26 AM
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#246
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Newbie Group: Members Posts: 17 Joined: 8-September 15 Member No.: 7773 |
Science article
Some new results from SAM discussed in this article : some samples are enriched in light Carbon. |
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Lo-Fi Version | Time is now: 26th September 2024 - 08:39 PM |
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