Yes, that's one of many possible habitats for life there.
Mars originally had lots of water, perhaps several hundred meters or even a kilometer or more average depth.
Nobody yet knows for sure how much is left (some surely lost to space for instance). Depending how much, it could have a deep "hydrosphere" several kilometers below the surface. At depth it gets hotter through geothermal heat just like Earth. So at sufficient depth - so long as there is water trapped there - it would be liquid - and it would be kept under pressure by the rocks overhead so would not evaporate and would have normal boiling point. It could be tens of meters or a hundred meters in thickness.
Mars surface, though the total amount of water is surely small, still has flowing water at times depending on axial tilt, when the atmosphere gets a bit thicker, enough for liquid water to be stable at least temporarily - enough to form gullies as recently as 500,000 years ago.
It also has ice covered lakes that form after an impact or volcanic activity.
None at present as far as we know, but about 210 million years ago it had a couple of lakes on flanks of Arsia Mons of about 40 cubic kilometers each, and a third one of 20 cubic kilometers which remained liquid for between centuries up to perhaps of the order of thousands of years.
There could be water like that at shallower levels below the surface on a smaller scale due to geothermal activity - just needs to be trapped in a cave or by impervious rocks above to keep it liquid. One of the many hypotheses for the RSLs is that they could be surface seeps from geothermal sources, possibly fed all the way from the deep hydrosphere.
Includes also the possibility of serpentization - creation of methane from basalt and water - so the methane plumes could be the result of that - or of life - or of release of methane from clathrates created in ancient times.
Indeed there could also be fumaroles on the surface - which are ice covered volcanic vents - would be hard to spot from orbit as the ice would make them the same temperature as their surroundings.
The interior of Mars is molten rock like Earth. It doesn't have continental drift - Valles Marineres may be the scar of an early "attempt" at splitting into plates which failed. A planet could have a molten core without volcanism, just steady loss of heat through its crust. Callisto would be an example of an object believed to be hot inside, in that case with a liquid water ocean below the ice,and hot rock below that - but no visible effect on its present day surface.
But Mars is still geologically active also, signs that show that its volcanoes have erupted in the past - and could continue to so in the future. And present day activity is not ruled out, could be very small scale geological activity not visible from orbit.
This is about the search for present day activity on Mars, the ESA trace gas orbiter launched in 2016 will search for volcanic activity as well as traces of organics possibly indicating new habitats on Mars.
The Search For Volcanic Eruptions On Mars Reaches The Next Level - Astrobiology Magazine
For more ideas, see Are There Habitats For Life On Mars? - Salty Seeps, Clear Ice Greenhouses, Ice Fumaroles, Dune Bioreactors,...
Mars originally had lots of water, perhaps several hundred meters or even a kilometer or more average depth.
Nobody yet knows for sure how much is left (some surely lost to space for instance). Depending how much, it could have a deep "hydrosphere" several kilometers below the surface. At depth it gets hotter through geothermal heat just like Earth. So at sufficient depth - so long as there is water trapped there - it would be liquid - and it would be kept under pressure by the rocks overhead so would not evaporate and would have normal boiling point. It could be tens of meters or a hundred meters in thickness.
Mars surface, though the total amount of water is surely small, still has flowing water at times depending on axial tilt, when the atmosphere gets a bit thicker, enough for liquid water to be stable at least temporarily - enough to form gullies as recently as 500,000 years ago.
It also has ice covered lakes that form after an impact or volcanic activity.
None at present as far as we know, but about 210 million years ago it had a couple of lakes on flanks of Arsia Mons of about 40 cubic kilometers each, and a third one of 20 cubic kilometers which remained liquid for between centuries up to perhaps of the order of thousands of years.
There could be water like that at shallower levels below the surface on a smaller scale due to geothermal activity - just needs to be trapped in a cave or by impervious rocks above to keep it liquid. One of the many hypotheses for the RSLs is that they could be surface seeps from geothermal sources, possibly fed all the way from the deep hydrosphere.
Includes also the possibility of serpentization - creation of methane from basalt and water - so the methane plumes could be the result of that - or of life - or of release of methane from clathrates created in ancient times.
Indeed there could also be fumaroles on the surface - which are ice covered volcanic vents - would be hard to spot from orbit as the ice would make them the same temperature as their surroundings.
The interior of Mars is molten rock like Earth. It doesn't have continental drift - Valles Marineres may be the scar of an early "attempt" at splitting into plates which failed. A planet could have a molten core without volcanism, just steady loss of heat through its crust. Callisto would be an example of an object believed to be hot inside, in that case with a liquid water ocean below the ice,and hot rock below that - but no visible effect on its present day surface.
But Mars is still geologically active also, signs that show that its volcanoes have erupted in the past - and could continue to so in the future. And present day activity is not ruled out, could be very small scale geological activity not visible from orbit.
This is about the search for present day activity on Mars, the ESA trace gas orbiter launched in 2016 will search for volcanic activity as well as traces of organics possibly indicating new habitats on Mars.
The Search For Volcanic Eruptions On Mars Reaches The Next Level - Astrobiology Magazine
For more ideas, see Are There Habitats For Life On Mars? - Salty Seeps, Clear Ice Greenhouses, Ice Fumaroles, Dune Bioreactors,...
About the Author
Robert Walker
Writer of articles on Mars and Space issues - Software Developer of Tune Smithy, Bounce Metronome etc.Studied at Wolfson College, Oxford
Lives in Isle of Mull
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