• We have updated the guidelines regarding posting political content: please see the stickied thread on Website Issues.

Water On Mars

Newly published research suggests brines may not be as widespread as previously believed. If true, this could have a major impact on planning for future Mars missions and the prospects for eventual Mars colonization.
Water on Mars not as widespread as previously thought, study finds

Water on Mars, in the form of brines, may not be as widespread as previously thought, according to a new study by researchers at the Arkansas Center for Space and Planetary Sciences.

Researchers combined data on brine evaporation rates, collected through experiments at the center's Mars simulation chamber, with a global weather circulation model of the planet to create planetwide maps of where brines are most likely to be found. ...

The scientists took all major phase changes of liquids into account -- freezing, boiling and evaporation - instead of just a single phase, as has commonly been the approach in the past, said Vincent Chevrier, associate professor and first author of a study published in The Planetary Science Journal. ...

"It is looking at all the properties at the same time, instead of one at a time," said Chevrier. "Then we build maps taking into account all those processes simultaneously."

Doing so indicates that previous studies may have overestimated how long brines remain on the surface in the cold, thin and arid Martian atmosphere, Chevrier said. "The most important conclusion is that if you do not take all these processes together, you always overestimate the stability of brines. That is the reality of the situation."

Favorable conditions for stable brines on the planet's surface are most likely to be present in mid- to high-northern latitudes, and in large impact craters in the southern hemisphere, he said. In the shallow subsurface, brines might be present near the equator. ...
Click to expand...

FULL STORY:
https://www.eurekalert.org/pub_releases/2020-12/uoa-wom121020.php

PUBLISHED REPORT:
Global Temporal and Geographic Stability of Brines on Present-day Mars
https://iopscience.iop.org/article/10.3847/PSJ/abbc14
 
Possible good news for future colonists.

By Earth standards, the surface of Mars is the picture of desolation.

It's not only irradiated and cold enough to make Antarctica look balmy, but it's also one-thousands times drier than the driest places on Earth. However, beneath the super-arid surface of the Red Planet, there are abundant supplies of water ice that could someday be accessible to human explorers (and even settlers).

This is especially the case in the mid-latitude region known as Arcadia Planitia, a smooth plain located in Martian northern lowlands. According to new research conducted with support from NASA's Jet Propulsion Laboratory (JPL), the region shows signs of glaciers and glacier activity. These findings could prove very useful for the future human landings and exploration of Mars, not to mention potential settlement.

The study, which recently appeared in the scientific journal Icarus, was led by Shannon Hibbard—a Ph.D. candidate in geology and planetary science at the University of Western Ontario (UWO). She was joined by Dr. Gordon R. Osinski of UWO's Institute for Earth and Space Exploration (IESE), and Etienne Godin, a data scientist at the Center for Northern Studies at Laval University; and Nathan Williams and Matthew Golombek of NASA JPL. ...

https://phys.org/news/2021-05-mid-latitude-glaciers-mars-human-explorers.html
 
Here's some more info on what may be ice flows (analogous to thinly-buried glaciers) in the Arcadia Planitia region.
Possible new type of glacier just discovered on Mars

A potential Mars landing site might be underlain by debris-covered glaciers.

Strange sinuous features on a flat plain known as Arcadia Planitia bear a striking resemblance to ice streams within ice sheets in Antarctica, a new study finds. If these shallowly covered glaciers do, in fact, exist, they could be a reason to direct future crewed missions to Mars toward the region. The spot was already intriguing to SpaceX and NASA because it is a broad, flat plain, which is ideal for landing spacecraft. If there is ice not too deep below the surface of the plain, astronauts could also have a water source easily at hand.

The newfound flow-like features are strange because they occur on flat terrain ...
Click to expand...
FULL STORY: https://www.livescience.com/mars-arcadia-planitia-glaciers.html
 
Just a Mars Mirage?

Maybe hold off on that Martian ice fishing trip.

Two new studies splash cold water on the idea that potentially habitable lakes of liquid water exist deep under the Red Planet’s southern polar ice cap.

The possibility of a lake roughly 20 kilometers across was first raised in 2018, when the European Space Agency’s Mars Express spacecraft probed the planet’s southern polar cap with its Mars Advanced Radar for Subsurface and Ionosphere Sounding, or MARSIS, instrument. The orbiter detected bright spots on radar measurements, hinting at a large body of liquid water beneath 1.5 kilometers of solid ice that could be an abode to living organisms (SN: 7/25/18). Subsequent work found hints of additional pools surrounding the main lake basin (SN: 9/28/20).

But the planetary science community has always held some skepticism over the lakes’ existence, which would require some kind of continuous geothermal heating to maintain subglacial conditions (SN: 2/19/19). Below the ice, temperatures average –68° Celsius, far past the freezing point of water, even if the lakes are a brine containing a healthy amount of salt, which lowers water’s freezing point. An underground magma pool would be needed to keep the area liquid — an unlikely scenario given Mars’ lack of present-day volcanism.

https://www.sciencenews.org/article/mars-lakes-liquid-water-south-pole-ice-cap-mirages
 
ramonmercado said:
Just a Mars Mirage?

Maybe hold off on that Martian ice fishing trip.

Two new studies splash cold water on the idea that potentially habitable lakes of liquid water exist deep under the Red Planet’s southern polar ice cap.

The possibility of a lake roughly 20 kilometers across was first raised in 2018, when the European Space Agency’s Mars Express spacecraft probed the planet’s southern polar cap with its Mars Advanced Radar for Subsurface and Ionosphere Sounding, or MARSIS, instrument. The orbiter detected bright spots on radar measurements, hinting at a large body of liquid water beneath 1.5 kilometers of solid ice that could be an abode to living organisms (SN: 7/25/18). Subsequent work found hints of additional pools surrounding the main lake basin (SN: 9/28/20).

But the planetary science community has always held some skepticism over the lakes’ existence, which would require some kind of continuous geothermal heating to maintain subglacial conditions (SN: 2/19/19). Below the ice, temperatures average –68° Celsius, far past the freezing point of water, even if the lakes are a brine containing a healthy amount of salt, which lowers water’s freezing point. An underground magma pool would be needed to keep the area liquid — an unlikely scenario given Mars’ lack of present-day volcanism.

https://www.sciencenews.org/article/mars-lakes-liquid-water-south-pole-ice-cap-mirages
Click to expand...
Just wait for a while. There'll be yet another announcement of ice or water on Mars.
 
From an article this year:

https://www.caltech.edu/about/news/what-happened-to-marss-water-it-is-still-trapped-there

around four billion years ago, Mars was home to enough water to have covered the whole planet in an ocean about 100 to 1,500 meters deep; a volume roughly equivalent to half of Earth's Atlantic Ocean. But, by a billion years later, the planet was as dry as it is today.

According to new research from Caltech and JPL, a significant portion of Mars's water—between 30 and 99 percent [a large difference]—is trapped within minerals in the planet's crust. The research challenges the current theory that the Red Planet's water escaped into space.
Click to expand...

Some of it was lost to the atmosphere - they looked for traces of deuterium in the atmosphere but didn't find enough to show a lot of water escaping to space due to Mars' weak gravity, therefore a large amount of the water is still on the planet. They explain it by the trapping of water in minerals in the planet's crust.
 
ramonmercado said:
Two new studies splash cold water on the idea that potentially habitable lakes of liquid water exist deep under the Red Planet’s southern polar ice cap. ...
Click to expand...

This newly-published research provides further evidence suggesting recent claims of large sub-surface ice or water bodies on Mars may be over-optimistic. In this case, the researchers determined the radar readings suggestive of liquid water maybe instead represent volcanic rocks.
Mysterious Signal of Hidden Lakes on Mars May Not Be What We Thought

The likelihood of lakes of liquid water hidden under Mars' southern polar ice cap is receding before our very eyes.

Last year, a paper found that temperatures were likely far too cold for water to remain unfrozen in the region. Now, a new study has found that the radar signal interpreted as liquid water was likely another resource Mars has in abundance: volcanic rock. ...
Click to expand...
FULL STORY: https://www.sciencealert.com/liquid...-cap-was-probably-just-rock-new-study-reveals

FULL RESEARCH REPORT: https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2021GL096518
 
EnolaGaia said:
This newly-published research provides further evidence suggesting recent claims of large sub-surface ice or water bodies on Mars may be over-optimistic. In this case, the researchers determined the radar readings suggestive of liquid water maybe instead represent volcanic rocks. ...
Click to expand...

This newer article describes how researchers have demonstrated the highly-reflected radar signals that were the basis for believing there are sub-surface masses of water at the Martian south pole can be explained by layered rocks rather than water. This doesn't prove there's no water at Mars' south pole, but it does call the prevailing presumption into question.
Shimmering 'Lakes' Under The South Pole of Mars Might Be Something Else Entirely

What scientists thought were lakes of liquid water hiding under the southern polar ice cap of Mars could turn out to be… just regular old rock.

New analysis has found that the brightly shining radar signal interpreted as underground water on the red planet could also have been produced by geological layering. It's not a foregone conclusion, but it does suggest that stronger evidence is needed before we can determine with any certainty what's lurking under there.

"Here we demonstrate that similar reflections can be generated as the natural result of thin layer interference, without invoking any liquid water or otherwise rare materials," write a team of researchers led by astronomer Dan Lalich of Cornell University in a new paper.

"This result, combined with other recent work, calls into question the likelihood of finding liquid water below the south polar layered deposit (SPLD)." ...
Click to expand...
FULL STORY: https://www.sciencealert.com/shimme...pole-of-mars-might-be-something-else-entirely
 
Will water flow on Mars again?

Ravine-like channels on Mars are something of a puzzle. They look like the gullies in Antarctica caused by melting glaciers, but the elevated locations of many of the features aren't places we'd expect to find recently flowing water.

So how did these Mars gullies form? Sublimating carbon dioxide ice has been put forward as an alternative hypothesis, but a new study by a team of scientists in the US suggests that in the right conditions, liquid water really could do the job. What's more, it could've happened recently as far as geological timescales go, maybe just 630,000 years ago.

The key is the tilt of the planet's axis. When that tilt gets to 35 degrees, the new simulation of temperature and circulation shows, the density of the atmosphere would cause the surface to heat up above freezing point, briefly. It would be enough to melt some of the snow and ice that is still on Mars.

"We know from a lot of our research and other people's research that early on in Mars history, there was running water on the surface with valley networks and lakes," says Brown University planetary scientist Jim Head.

"But about 3 billion years ago, all of that liquid water was lost, and Mars became what we call a hyper-arid or polar desert."

https://www.sciencealert.com/recent...-could-flow-on-the-planet-again-in-the-future
 
Plenty of water, only 3.7km underground.

A European Space Agency (ESA) probe has found enough water to cover Mars in an ocean between 4.9 and 8.9 feet (1.5 and 2.7 meters) deep, buried in the form of dusty ice beneath the planet's equator.

The finding was made by ESA's Mars Express mission, a veteran spacecraft that has been engaged in science operations around Mars for 20 years now. While it's not the first time that evidence for ice has been found near the Red Planet's equator, this new discovery is by far the largest amount of water ice detected there so far and appears to match previous discoveries of frozen water on Mars.

"Excitingly, the radar signals match what we expect to see from layered ice and are similar to the signals we see from Mars' polar caps, which we know to be very ice rich," said lead researcher Thomas Watters of the Smithsonian Institution in the United States in an ESA statement.

The deposits are thick, extended 3.7km (2.3) miles underground, and topped by a crust of hardened ash and dry dust hundreds of meters thick. The ice is not a pure block but is heavily contaminated by dust. While its presence near the equator is a location more easily accessible to future crewed missions, being buried so deep means that accessing the water-ice would be difficult.

Some 15 years ago, Mars Express detected deposits beneath a geological formation called the Medusae Fossae Formation (MFF), but scientists were not sure what those deposits consisted of. Mars' geography is split between northern highlands and southern lowlands, and the huge 5,000-km-long MMF is situated near the boundary between the two. ...

https://www.livescience.com/space/m...-of-frozen-water-found-buried-at-mars-equator
 
You must log in or register to reply here.
Back
Top