List of evidence for water on Mars |
List of evidence for water on Mars |
Feb 28 2013, 11:55 AM
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#16
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Member Group: Members Posts: 813 Joined: 29-December 05 From: NE Oh, USA Member No.: 627 |
There was a conference earlier this month at UCLA on Mars Habitability: link below
http://planets.ucla.edu/meetings/mars-habi...y-2013/program/ Day One sessions include fascinating presentations on the possibility of transient liquid water near the surface today. Alfred McEwen gives a 30 min update on Mars RSL (Recurring Slope Lineae). They are now identifying sites at Vallis Marineris that track the sun. Also updates on Phoenix results are presented. Chemistry of perchlorates…. There are video and pdfs for most of the talks. Two examples: Behavior of Briny water at the Phoenix Landing site https://connect.arc.nasa.gov/p4cbkn97lbv/?l...p;pbMode=normal Recurring Slope Lineae (RSL): Flow of Briny Water on Present day Mars https://connect.arc.nasa.gov/p27eg800f7b/?l...p;pbMode=normal Craig |
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Jul 3 2014, 11:12 PM
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#17
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Member Group: Members Posts: 401 Joined: 5-January 07 From: Manchester England Member No.: 1563 |
Pardon the thread necromancy, but this seems like the best place to mention this paper from the university of Michegan. They demonstrate, using an environment chamber, a plausible mechanism whereby Martian ice could melt to form droplets of liquid water, under present day conditions.
For those without access, here's the press release. My main criticism is that the salts used here only occur as a few percent by weight in any Martian soils we have examined. Nothing rules out higher concentrations, but fairly finely distributed grains of such salts would make Mars very mildly damp, not wet! -------------------- |
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Jul 4 2014, 07:52 AM
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#18
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Senior Member Group: Members Posts: 1057 Joined: 17-February 09 Member No.: 4605 |
Not even mildly damp. With 1 to 2% of perchlorate found in the regolith by Phoenix this experiment where perchlorate salt is layered over ice hardly represents a simulation. Forgive my cynicism but the analogy would be using a high pressure fire hose to simulate a light drizzle to prove that spray jackets are ineffective. The TECP effectively confirmed that no brine was present in the regolith.
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Jul 4 2014, 04:19 PM
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#19
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Member Group: Members Posts: 401 Joined: 5-January 07 From: Manchester England Member No.: 1563 |
There's certainly nothing to forgive, I think your skepticism is entirely warranted! But, if we look past the iffy connection to the phoenix mission and its 'blobs', I think this is a meaningful piece of experiment - even if the interpretation isn't all it might be: Such salts as are found on Mars can interact with near surface ice to produce liquid, even under current atmospheric conditions. If soils with much higher concentrations of such salts are ever found, or existed in the past, then such brine-y dampness might have played a role in the history of some areas. And ruling out the idea of deliquesence leading to the formation of surface liquid, even in highly salty soils, is a useful result to.
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Apr 9 2015, 11:43 AM
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#20
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Member Group: Members Posts: 495 Joined: 12-February 12 Member No.: 6336 |
Studies done at Niels Bohr institute in Copenhagen have found that Mars has belts of glaciers consisting of frozen water.
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Apr 9 2015, 04:21 PM
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#21
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Member Group: Members Posts: 401 Joined: 5-January 07 From: Manchester England Member No.: 1563 |
This makes me wonder: If ice, at a lattitude and altitude that put temperature and pressure in the 'liquid water range', were exposed ona sunwards facing slope today (by landslide, impact, man digging with shovel, whatever) how much hydration would the immediate surroundings actually get? Because, as I understand it, even when Martian conditions are at their most water-favourable only small amounts would form, and only briefly.
I could believe however that a liquid water pocket(s) might form beneath the translucent surface of said exposed ice, and find its way surfacewards - but it still seems as though the surroundings wouldn't get very 'wet'. I do recall experiments with pure ice under martian conditions being done, but cannot find them Of course 'chemically enhanced' (antifreeze of some kind laden) water would be more stable.... -------------------- |
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Apr 10 2015, 09:09 AM
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#22
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Member Group: Members Posts: 495 Joined: 12-February 12 Member No.: 6336 |
On Earth you will often find water under a glacier, on Mars the temperature is lower so it might only happen under special conditions, and if the glacier is on top of an area with a lot of salts such brine is then potentially possible.
Since Mars is thought to be in a current ice age, this report also adds a piece to the puzzle on where the 'missing' water ended up. Some images from orbit have shown what might be comparatively recent water flows, with only few or nearly no craters. So I found this interesting since these glaciers might be part of the hydrological cycle when the climate switch to a more benign state. |
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Apr 12 2015, 12:41 AM
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#23
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Senior Member Group: Members Posts: 1057 Joined: 17-February 09 Member No.: 4605 |
A glacier is by definition dynamic. So are they claiming that the ice is still moving under regolith or are they identifying relict, now static deposits? The presence of huge mid to high latitude ice deposits was confirmed by Odyssey and much evidence of glaciation has been revealed over the years. If they have identified active glaciation under the insulating cover (movement of existing deposits under gravity but without any replenishment) then this is indeed a stunning discovery. Otherwise it is just a variation on a theme.
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Apr 13 2015, 07:26 PM
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#24
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Member Group: Members Posts: 293 Joined: 22-September 08 From: Spain Member No.: 4350 |
"Transient liquid water and water activity at Gale crater on Mars"
http://www.nature.com/ngeo/journal/vaop/nc...l/ngeo2412.html |
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Apr 14 2015, 01:32 PM
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#25
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Junior Member Group: Members Posts: 78 Joined: 20-September 14 Member No.: 7261 |
EGU 2015 Press Conference 5: "Water Signatures on the Martian Surface"
Basically three different teams presenting findings on various particular surface forms shaped by water they're searching for. |
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Apr 17 2015, 10:36 AM
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#26
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Member Group: Members Posts: 495 Joined: 12-February 12 Member No.: 6336 |
If they have identified active glaciation under the insulating cover (movement of existing deposits under gravity but without any replenishment) then this is indeed a stunning discovery. Otherwise it is just a variation on a theme. You are right, and from the press release I was not able to determine if it was to be read as if they had found actual changes, though we now do have image resolution that would make it potentially possible to detect such movements. So I did not make any speculation but only listed the press release at first, but in the follow up post after marsbug I did mention the possibility of water under such glaciers since - at least on Earth - water lessen the friction in the underlying rocks, sand and gravel so that the glacier can move. Glaciers on Earth often ends with a flow of water, but I do not expect any such to reach the surface of Mars now these are buried. Perhaps it would be possible to detect an elevated level of humidity of water vapour to show that there's some water beneath. -Anyhow it seem that the paper is written by a post-doc, so it might indeed be a "variation of a theme", where she's testing the water in the scientific publication world for the first time. =) |
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Apr 17 2015, 07:08 PM
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#27
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Junior Member Group: Members Posts: 78 Joined: 20-September 14 Member No.: 7261 |
Glaciers on Earth often ends with a flow of water, but I do not expect that on Mars now these are buried. I haven't really read that much more than the abstract, but this paper on interaction between buried glaciers, permafrost ground and intrasedimental ice (on Earth) might be helpful. |
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Sep 26 2015, 06:10 PM
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#28
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Senior Member Group: Members Posts: 1669 Joined: 5-March 05 From: Boulder, CO Member No.: 184 |
Will Monday's announcement be about further water evidence?
http://www.jpl.nasa.gov/news/news.php?feature=4720 -------------------- Steve [ my home page and planetary maps page ]
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Sep 27 2015, 06:03 AM
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#29
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Junior Member Group: Members Posts: 23 Joined: 24-August 07 Member No.: 3405 |
Rumor suggests a discovery of flowing water. I would think that the low air pressure would cause water to just boil off.
Will Monday's announcement be about further water evidence? http://www.jpl.nasa.gov/news/news.php?feature=4720 |
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Sep 27 2015, 06:39 AM
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#30
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Merciless Robot Group: Admin Posts: 8785 Joined: 8-December 05 From: Los Angeles Member No.: 602 |
If that has any validity it would probably be a reference to the slope streaks; not flowing open water, and very transient (whatever they actually turn out to be.).
However, as you said, it's just a rumor. Could be a few other things instead. We'll know on Monday. -------------------- A few will take this knowledge and use this power of a dream realized as a force for change, an impetus for further discovery to make less ancient dreams real.
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