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OWW
The captions of the latest Odyssey images ( 31 January 2005 and later ) neglect to mention their locations...

http://themis.asu.edu/latest/

I have no idea where these were taken. Noctis Labyrintus or the chaotic terrain? Is there a walking mars atlas in the room here? laugh.gif
deglr6328
The other THEMIS mystery images... huh.gif About 2 years ago there was a (minor) to do about some images taken by THEMIS in the Hellas basin region which seemed to show anomalously high surface temperatures at night. (I hate linking to New Sensationalist but they have that cool picture...) U. Melbourne geologist Nick Hoffman seemed to think they were "ice towers", geothermal vents under the ice pack. Then, I never heard another thing about it. I would think that this being (so far as I know) the only thermal anomaly odyssey has found, it would be investigated further. This was one of the reasons for sending mid/far IR imagers, right? It is worth noting that the person behind the ice tower theory is the same guy who staunchly stands by his conviction of a completely dry Mars. The so called "white mars" theory, where all geologic weathering conventionally atributed to past water flow is, in his model, attributed to "non-conventional volatile models" eg. CO2 liquid flow. It would seem that with the new overwhelming evidence for water provided by the MERs that this theory should be dead and buried. His website hasn't been updated since the gusev landing. Oh, and good luck trying to slog through all the conspiracist crap on this one in order to find real information. It's not easy or fun. mad.gif
gorelick
QUOTE (deglr6328 @ May 9 2005, 04:58 PM)
The other THEMIS mystery images... huh.gif  About 2 years ago there was a (minor) to do about some images taken by THEMIS in the Hellas basin region which seemed to show anomalously high surface temperatures at night. (I hate linking to New Sensationalist but they have that cool picture...) U. Melbourne geologist Nick Hoffman seemed to think they were "ice towers", geothermal vents under the ice pack. Then, I never heard another thing about it. I would think that this being (so far as I know) the only thermal anomaly odyssey has found, it would be investigated further. This was one of the reasons for sending mid/far IR imagers, right?  It is worth noting that the person behind the ice tower theory is the same guy who staunchly stands by his conviction of a completely dry Mars. The so called "white mars" theory, where all geologic weathering conventionally atributed to past water flow is, in his model, attributed to "non-conventional volatile models" eg. CO2 liquid flow.  It would seem that with the new overwhelming evidence for water provided by the MERs that this theory should be dead and buried. His website hasn't been updated since the gusev landing. Oh, and good luck trying to slog through all the conspiracist crap on this one in order to find real information. It's not easy or fun.  mad.gif
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This was a silly fuss about nothing. Hoffman originally thought he found some "vents" that were +20C to +40C over their surroundings, however it turns out that he was simply unable to read the data properly. What he "found" was a couple of small (~500m) warm spots (+8 degC), however that's not at all surprising, since there are places all over mars where there's exposed rock outcroppings that are +10C to +15C warmer than their surroundings.

In reality, THEMIS hasn't found even the slightest hint of active hydrothermal or volcanic activity.
deglr6328
hm! rolleyes.gif how did you find this stuff out?!
gorelick
QUOTE (deglr6328 @ May 9 2005, 08:48 PM)
hm! rolleyes.gif            how did you find this stuff out?!
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Which part?

I reviewed Hoffman's paper right before he presented it at the Mars 6th conference, and pointed out the errors. I think he still presented it, but with the revised numbers. To his credit, the central tenet of his paper was: "If there are vents on Mars, they could be ice towers like those found in Antarctica", and the actual lack of evidence of vents doesn't make that false.

I know THEMIS hasn't found any thermal anomalies because I'm one of the authors on the THEMIS results paper in Science that says: "To date, however, no temperatures have been identified that cannot be attributed to thermophysical properties (e.g., bedrock or dust exposures) alone."
deglr6328
neato. I hope you didn't think I was doubting you though, I was just curious. Its such an obscure topic. smile.gif Thank you for the info!
BruceMoomaw
As for Nick Hoffman (a longtime member of the invitation-only Planetary Sciences Webgroup of which I'm a member), he is indeed backpedaling like mad (at least in his E-mails) on his original view that liquid water played no significant role in Martian surface geology. He still thinks, however, that it may have played a relatively small role, and then only because it was both acidic and salty as all get-out, which greatly lowered its freezing temperature -- and on those points he may well be right.
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