Mars could have enough molecular oxygen to support life, and scientists figured out where to find it

October 22, 2018 by Deborah Netburn, Los Angeles Times
The new research was made possible by the discovery by NASA's Curiosity Mars rover of manganese oxides

Modern-day Mars may be more hospitable to oxygen-breathing life than previously thought.

A new study suggests that salty water at or near the surface of the red planet could contain enough dissolved O2 to support oxygen-breathing microbes, and even more complex organisms such as sponges.

"Nobody thought of Mars as a place where aerobic respiration would work because there is so little oxygen in the atmosphere," said Vlada Stamenkovic an Earth and planetary scientist at the Jet Propulsion Laboratory who led the work. "What we're saying is it is possible that this planet that is so different from Earth could have given aerobic life a chance."

As part of the report, Stamenkovic and his coauthors also identified which regions of Mars are most likely to contain brines with the greatest amounts of dissolved oxygen. This could help NASA and other space agencies plan where to send landers on future missions, they said.

The work was published Monday in Nature Geoscience.

On its surface, the planet Mars is not what you would consider a hospitable place for most Earthlings.

Here on Earth, 21 percent of our atmosphere is made up of oxygen—thanks to the abundance of plants and other organisms that create oxygen as a byproduct of photosynthesis.

The Martian atmosphere, on the other hand, is made up of just .145 percent oxygen, according to data collected by the Mars rovers.

With no plants to make O2, the minuscule amount of oxygen on Mars is created when radiation from the sun interacts with CO2 in the planet's atmosphere.

In addition, Mars' atmosphere is extremely thin—160 times thinner than Earth's atmosphere. In addition, the temperature at the surface frequently drops to minus 100, making it extremely difficult for liquid water to exist on the planet's surface.

Pure liquid water would either freeze or evaporate away on Mars, but salty water, or brines, could remain in a liquid state at or just below the surface of the planet, the authors said. That's because water mixed with salts has a lower freezing temperature than plain water. (That's why those unfortunate people who live in cold climates use salt to melt the ice on their sidewalks.)

In the first part of the paper, the authors use computer models to show that water mixed with salts already present on Mars could be stable in a liquid state at or near the surface.

Once the authors were convinced that these liquid brines could exist, their next step was to determine how much dissolved oxygen they could absorb from the atmosphere.

"If there are brines on Mars, then the oxygen would have no choice but to infiltrate them," said Woody Fischer, a geobiologist at Caltech who worked on the study. "The oxygen would make it everywhere."

To calculate how much oxygen the brines might absorb, the researchers had to consider their chemistry, as well as the temperature and air pressure at the Martian surface. Brines will absorb more oxygen when the temperature is lower and the air pressure is higher.

Their results showed that modern Mars could support liquid environments with enough dissolved O2 to support oxygen-breathing microbes across the planet. They also found that the oxygen concentrations would be especially high in brines found at the polar regions, where temperatures are cooler.

So far, this work has been done through computer modeling. But experts still said that the study looks robust.

"The best studies that rely on models for their results conduct a thorough review of the possible variables that can influence the model output," said Kathleen Mandt, a planetary biologist at the Johns Hopkins University Applied Physics Laboratory. "This study does a good job at exploring a range of possible outcomes."

What the study doesn't do, however, is prove that there are indeed brines on Mars.

"What we know is that theoretically there should be brines on Mars, and that they would be able to dissolve enough oxygen to be biologically useful," Stamenkovic said.

The next step, he said, is two-fold.

He hopes that researchers here on Earth will do experiments to put oxygen-breathing microbes in the brines that could occur on Mars to find out what type of chemistry they do and whether they can thrive. The other step would be to send a lander to Mars that can look for brines from the shallow to the deep subsurface.

"Amazing work has been done by NASA to look for evidence of past habitable environments," he said. "I am a big promoter of looking for current habitable environments, and we can do that by starting to explore if there is liquid water on Mars."

To that end, Stamenkovic is working to develop a new tool, no bigger than a shoe box, that could be used to find water on Mars and determine its salinity, no digging necessary.

He calls it TH2OR.

Explore further: What on Earth could live in a salt water lake on Mars? An expert explains

More information: Vlada Stamenković et al. O2 solubility in Martian near-surface environments and implications for aerobic life, Nature Geoscience (2018). DOI: 10.1038/s41561-018-0243-0

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Mark Thomas
4.1 / 5 (9) Oct 22, 2018
In some locations, the amount of oxygen available could even keep alive a primitive, multicellular animal such as a sponge.


Add this to the mountain of reasons to go to Mars.

We have plenty of reasons to go, we have the technology or ability to develop it, we have the money (the world is not broke). When are we going to make this happen?
24volts
2.3 / 5 (12) Oct 22, 2018
I still say we should stop worrying about whether life used to live there and start putting some there. It's going to take a long time to terraform that planet as it is. The sooner we get started the better.
Osiris1
2.3 / 5 (3) Oct 22, 2018
there is a lot of water on Mars, every bit of which contains O2 for breathing and H2 for portable fuel. With reaction: 2(H2o) --> 2(H2) +O2
jonesdave
3.9 / 5 (14) Oct 22, 2018
I still say we should stop worrying about whether life used to live there and start putting some there. It's going to take a long time to terraform that planet as it is. The sooner we get started the better.


So, screw the possibility of probably the most significant finding in the history of mankind - the discovery of extraterrestrial life? Trust me, that is not going to happen.
Surveillance_Egg_Unit
1.4 / 5 (11) Oct 22, 2018
It is still in the planning stage now. There seems to be quite a dearth of volunteers to become the 'astronauts/settlers/guinea pigs' who long to get off Earth and build a new home on Mars. Oh, and to do a little bit of science while they're at it.

And SpookyOtto should be along soon to tell us about the 900 foot long martians with the glassy eyes or glassy something that he has seen on Mars.. It is always an interesting tale to know that SpookyOtto has seen life on Mars that scientists have never known about.
Waiting 1 -- 2 -- 3 --
Surveillance_Egg_Unit
1.4 / 5 (9) Oct 22, 2018
I still say we should stop worrying about whether life used to live there and start putting some there. It's going to take a long time to terraform that planet as it is. The sooner we get started the better.
says 24volts

But 24 - think of the possibility that, after landing on Mars, a dozen or more of SpookyOtto's 900 foot long glassy eyed monsters/martians attacks our little band of astronauts/settlers/guinea pigs and tosses them onto the grill. There is no predicting what might lay in wait that may be larger than an amoeba that could crawl into the space suits of our young guinea pi - uh settlers/ astronauts.
Hawking said that humans need to get off this planet and go somewhere else. He might have wanted to join them, but his disability prevented it. And so, he could only dream about it.
Thorium Boy
1 / 5 (6) Oct 23, 2018
In some locations, the amount of oxygen available could even keep alive a primitive, multicellular animal such as a sponge.


Add this to the mountain of reasons to go to Mars.

We have plenty of reasons to go, we have the technology or ability to develop it, we have the money (the world is not broke). When are we going to make this happen?


Hook, line and sinker.
Parsec
4.2 / 5 (5) Oct 23, 2018
Oxygen is pure poison to anaerobic bacteria. They not require any level of oxygen. None at all. In fact, they require a level of exactly zero to survive.

Multicellular organisms on the other hand probably cannot subsist using anaerobic metabolisms because it is far less efficient and doesn't provide enough energy.

So this article doesn't make much sense to me.
barakn
3.7 / 5 (3) Oct 23, 2018
"Tiny marine animals that complete their life cycle in the total absence of light and oxygen are reported by Roberto Danovaro and colleagues" https://www.ncbi....2859860/
Whydening Gyre
2 / 5 (1) Oct 23, 2018
If there IS any form of life on Mars, it's already dying out slowly, anyway...
Any introduction of new species will prob'ly kill it off even faster (that seems to be the rule of thumb for invasive species).
With any luck a new introduction will result in hybrid species occurring,....
Mark Thomas
4.2 / 5 (5) Oct 24, 2018
Hook, line and sinker.


Says the fool who wrote, "There is no extinction."

https://phys.org/...ery.html

Spouting off false or illogical garbage does not make you a great orator, although it can make you president of the United States. The simple fact is if we never get beyond low Earth orbit (LEO), we are doomed. Even with the problem of global warming solved in some better future, the sun will eventually cook the Earth as part of its normal life cycle.

The Earth is the cradle of humanity, but mankind cannot stay in the cradle forever.


- Konstantin Tsiolkovsky
Pooua
5 / 5 (2) Oct 24, 2018
If martian brine becomes oxygen-charged from the atmosphere, a situation the opposite that of Earth, I would expect the rate to be low, due to the low concentration in the martian atmosphere. That means that anything that consumes the oxygen in the brine at a high rate would soon exhaust the oxygen and then stop reacting. So, if there is oxygen-rich brine on Mars, then the martian brine probably doesn't have any life in it, unless some of that life has a way of enriching the oxygen in the brine. The martian atmosphere, alone, is not sufficient to keep an underwater biome oxygenated.
Ojorf
1.8 / 5 (6) Oct 25, 2018
Life does not have to be fast.
On Earth life is found kilometers down, things with super slow metabolisms.
There are micro organisms that divide only every 1000 years or so found in rock millions of years old.
If there ever was life on Mars I think there is a very good chance something would still be there.
Jayarava
3 / 5 (2) Oct 25, 2018
What we know about Mars is minimal but the surface and atmosphere are at chemical equilibrium and have been for millions of years. To the best of our knowledge, there is no life on Mars and there are no *signs of life* on Mars.
torbjorn_b_g_larsson
not rated yet Nov 11, 2018
Oxygen is an energy source (albeit poisonous).

"Tiny marine animals that complete their life cycle in the total absence of light and oxygen are reported by Roberto Danovaro and colleagues"


The Loricifera from anoxic sediments was later convincingly shown to be dead fragments.

There are micro organisms that divide only every 1000 years or so found in rock millions of years old.


Again, dead or dying cells in older sediments, I don't think they see cell division at all.

the surface and atmosphere are at chemical equilibrium


Except not fully so as the methane shows, and it is the crust - or brines - that interest people looking for life anyway.

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