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Water Under the Surface Of Mars

Dryson

Commodore
Commodore
With Mars having at least 20% of it's surface covered in water at one time in it's past some of that water would have found its way into underground caves or etched them out from the Martian landscape similar to how caves with water in them are only Earth.

Where do you think that the best location to find these underground caves would be located at?

How far underground do you think the caves would be and does the core of Mars emit enough heat from the core to heat the water underground to keep it in a liquid form or would the water be frozen?

I'm thinking that if there are underground caves on Mars with water in them exploring them would be like the movie Sanctum.

https://en.wikipedia.org/wiki/Sanctum_(film)

Except on Mars.
 
How far underground do you think the caves would be and does the core of Mars emit enough heat from the core to heat the water underground to keep it in a liquid form or would the water be frozen?

I have wondered several times about the effect of lower air pressure with respect to the prospects for liquid water under the ground in mars. I know on the surface it is too low for liquid water even if/when the temperature is high enough.

Some honest questions for anyone who knows:

Could caverns underground be naturally pressurized somehow? In places where they are not, would the water eventually just evaporate through the gaps until it was far enough away from a hypothetical heat source to freeze? If so, would it have the potential to seal off an area?
 
I wouldn't think so long-term. I'm no chemist, but doesn't water sublimate (i.e. transition from solid directly to gas) under low pressure? If so, then even if it formed a seal like you describe, it wouldn't last.
 
I wouldn't think so long-term. I'm no chemist, but doesn't water sublimate (i.e. transition from solid directly to gas) under low pressure? If so, then even if it formed a seal like you describe, it wouldn't last.


The frozen polar caps seem to be doing rather well at not sublimating. Could the same process exist underground as well as a similar process that keeps the frozen caps frozen and from sublimating would keep liquid water from sublimating as well?

I would thin that the further underground that the water is and seeing as how NASA has discovered methane pockets if methane was present at deeper levels and mixed with water would there be more than enough pressure created inside of a cave to keep the water from sublimating?
 
As to where Mars's former oceans went, there are some other possibilities, like permafrost and evaporation into outer space. The latter is evident from Mars's enrichment in deuterium relative to the Earth, about a factor of 5 for its atmosphere.
 
With Mars having at least 20% of it's surface covered in water at one time in it's past some of that water would have found its way into underground caves or etched them out from the Martian landscape similar to how caves with water in them are only Earth.

Where do you think that the best location to find these underground caves would be located at?

How far underground do you think the caves would be and does the core of Mars emit enough heat from the core to heat the water underground to keep it in a liquid form or would the water be frozen?

I'm thinking that if there are underground caves on Mars with water in them exploring them would be like the movie Sanctum.

https://en.wikipedia.org/wiki/Sanctum_(film)

Except on Mars.

Hi Dryson. I am a Mars scientist (no, really) - so I will give it a try. Forgive any typos, I am about to knock off for the night as it is late. However,...

"Where do you think that the best location to find these underground caves would be located at?"

This is a very good question and hard to answer. We already know there are caves on Mars. We have spotted them from space. The process that leads to the types of caves you are talking about however is not predictable on Mars. On Earth, what you are talking about happens mainly in Karst regions. Those are created originally by massive amounts of biologic activity that create massive carbonate deposits. Mars - so far - does not show signs of that. SO, predicting where caves may be is pretty difficult - and caves filled with water even more so.

"How far underground do you think the caves would be and does the core of Mars emit enough heat from the core to heat the water underground to keep it in a liquid form or would the water be frozen?"

Too far. I don't think the RD on Mars can keep water liquid anyplace near where you will find water in the subsurface. However, Mars is not as cold as many folks think. The Air temp does occasionally go over freezing (0C) and the surface (in the ground) temps in a number of regions are over freezing sometimes (in fact often). There is also evidence of liquid water "daylighting" in the sides of craters from time to time. Although, that water may be very saline - even a brine.

"I'm thinking that if there are underground caves on Mars with water in them exploring them would be like the movie Sanctum."

I have not watched that movie (nor did I visit the link). However, it is possible some micro environs exist on Mars like that. Not sure how likely - but possible.

The funny thing is that because of something called chemical kinetics, it is possible for environments on Mars to defy thermodynamics for periods of time. That is the reason many folks think 20% of the planet (or more)may have been water covered at some point billion+ years ago and could have remained as such for a billion+ years.
 
I have wondered several times about the effect of lower air pressure with respect to the prospects for liquid water under the ground in mars. I know on the surface it is too low for liquid water even if/when the temperature is high enough.

Some honest questions for anyone who knows:

Could caverns underground be naturally pressurized somehow? In places where they are not, would the water eventually just evaporate through the gaps until it was far enough away from a hypothetical heat source to freeze? If so, would it have the potential to seal off an area?

I will give you some more food for thought. In a cavern were there is no air movement (or not much), The water that vaporizes or evaporates will saturate the "air" above the water body quickly. And no more vaporization of evaporation can take place (it will be "locked down").

In an enclosed space, with enough volume of water, assuming the temp is above freezing, then evaporation and vaporization will come to equilibrium with condensation and the water will remain liquid (or some of it will). So yes - you can have an enclosed area - not even pressure sealed - where, if the temperature is high enough, there can be liquid water until the process of diffusion (part of chem kinetics) allows for the water vapor to escape. You don't need 1 atm or whatever. You do need some gravity - But Mars has some.
 
The frozen polar caps seem to be doing rather well at not sublimating.
So where is all this liquid CO2 on Mars you're hinting at?

---------------


In all fairness, the northern cap is not really shrinking (on Mars). At least not nearly as fast as our own (Scary - since Mars is a dead planet!).

That said, you bring up a good question. Why are there signs of even modern liquid water (H2O) on Mars but not liquid CO2?

Thermodynamic stability ranges.

And that is important - it actually relates to why water is so essential for life as we understand it currently and liquid CO2 is not.
 
So it's unlikely that Mars has lots of caves. That leaves permafrost, and permafrost requires a soil layer to soak up the water. That could be erosion soil, as on our planet, or else impact-created soil or regolith, as on the Moon.
 
So it's unlikely that Mars has lots of caves. That leaves permafrost, and permafrost requires a soil layer to soak up the water. That could be erosion soil, as on our planet, or else impact-created soil or regolith, as on the Moon.

Well, Mars may have a lot of caves, just not the kind normally associated with water.

There is certainly soil* on Mars. In fact there are sedimentary rocks. And there is almost certainly permafrost on Mars. We actually know there is subsurface liquid "water" on Mars, although how much and how often is a question.
The soil on Mars originated as a combination of physical, chemical, and impact erosion.

*in planetary science, soil is defined differently than in terrestrial geology or biology.
 
I have wondered several times about the effect of lower air pressure with respect to the prospects for liquid water under the ground in mars. I know on the surface it is too low for liquid water even if/when the temperature is high enough.

Some honest questions for anyone who knows:

Could caverns underground be naturally pressurized somehow? In places where they are not, would the water eventually just evaporate through the gaps until it was far enough away from a hypothetical heat source to freeze? If so, would it have the potential to seal off an area?

I will give you some more food for thought. In a cavern were there is no air movement (or not much), The water that vaporizes or evaporates will saturate the "air" above the water body quickly. And no more vaporization of evaporation can take place (it will be "locked down").

In an enclosed space, with enough volume of water, assuming the temp is above freezing, then evaporation and vaporization will come to equilibrium with condensation and the water will remain liquid (or some of it will). So yes - you can have an enclosed area - not even pressure sealed - where, if the temperature is high enough, there can be liquid water until the process of diffusion (part of chem kinetics) allows for the water vapor to escape. You don't need 1 atm or whatever. You do need some gravity - But Mars has some.

This answers my questions very well. Thanks! I have some follow up reading to do now. ;)
 
Coupled with this article regarding a 30,000 year old seed frozen in permafrost http://www.trekbbs.com/showthread.php?t=275821
the potential that cave of ice discovered on Mars might in fact contain similar frozen seeds as well.

I think that you have to give up on the "seeds" part and focus on the fact that such a place could harbor actual life. Seeds are part of an advanced life-form's reproductive cycle. It is far more likely that that if any life exists on Mars currently, it will be primitive. And, while water ice is promising, liquid water is far more promising. Further, 30 Kya is not enough for Mars. If it ever had any advanced life (HUGE if) it occurred over a billion years ago from what we currently understand. And by "advanced" I mean something like algae - that would be a very advanced lifeform for Mars.
 
This answers my questions very well. Thanks! I have some follow up reading to do now. ;)

A student of a guy named Derek Sears put a glass of water in a "Mars Chamber" as I recall about 10 years ago. That is a pretty big chamber he used (you can fit people in it). According to him it took over 15 minutes to "evaporate" even though thermodynamically it should have just "vaporized". What occurred was a diffusion limited system. Just above the water (because there was no "wind" in the chamber) a saturated layer stopped evaporation. This is Chem Kinetics at work and sometimes it appears to violate thermodynamics.

On Another subject - If you find a paper you would like to read - say on google scholar - PM me. I think I can justify within the TOS getting you a (very) limited number of papers.
 
There are lots of organisms that can survive suspended animation. The organisms' cellular machinery is essentially frozen in place, like from the organisms' water freezing or the organisms drying out.

Some bacteria make spores that can survive very harsh conditions. That has obvious implications for survival in borderline places like Mars. Here are some papers that were published in mainstream scientific journals:
Protection of bacterial spores in space, a contribution to the discussion on Panspermia. - PubMed - NCBI
Orig Life Evol Biosph. 2001 Dec;31(6):527-47.
Protection of bacterial spores in space, a contribution to the discussion on Panspermia.
Horneck G1, Rettberg P, Reitz G, Wehner J, Eschweiler U, Strauch K, Panitz C, Starke V, Baumstark-Khan C.

Spores of Bacillus subtilis were exposed to space in the BIOPAN facility of the European Space Agency onboard of the Russian Earth-orbiting FOTON satellite. The spores were exposed either in dry layers without any protecting agent, or mixed with clay, red sandstone, Martian analogue soil or meteorite powder, in dry layers as well as in so-called 'artificial meteorites', i.e. cubes filled with clay and spores in naturally occurring concentrations. After about 2 weeks in space, their survival was tested from the number of colony formers. Unprotected spores in layers open to space or behind a quartz window were completely or nearly completely inactivated (survival rates in most cases < or = 10(-6)). The same low survival was obtained behind a thin layer of clay acting as an optical filter. The survival rate was increased by 5 orders of magnitude and more, if the spores in the dry layer were directly mixed with powder of clay, rock or meteorites, and up to 100% survival was reached in soil mixtures with spores comparable to the natural soil to spore ratio. These data confirm the deleterious effects of extraterrestrial solar UV radiation. Thin layers of clay, rock or meteorite are only successful in UV-shielding, if they are in direct contact with the spores. The data suggest that in a scenario of interplanetary transfer of life, small rock ejecta of a few cm in diameter could be sufficiently large to protect bacterial spores against the intense insolation; however, micron-sized grains, as originally requested by Panspermia, may not provide sufficient protection for spores to survive. The data are also pertinent to search for life on Mars and planetary protection considerations for future missions to Mars.
In short, a spore can survive very well if it is protected from solar ultraviolet light.

That paper's PubMed page links to related paper' PubMed pages, so if you want to find out more, that's a place to look.
 
So is that bad in that there might be surviving spores on Mars that are going to screw with us some day, or good in that it might be easier for us to seed Mars with things more to our liking? :)

Given the squirrel thread, if Mars ever had life of some sort, I'd say there's likely a couple timebombs waiting for us there...
 
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