Scientists find likely source of methane on Mars

The presence of methane has long been a point of contention among Mars experts
The presence of methane has long been a point of contention among Mars experts

The mystery of methane on Mars may finally be solved as scientists Monday confirmed the presence of the life-indicating gas on the Red Planet as well as where it might have come from.

In the 15 years since a European probe reported traces of the gas in the Martian atmosphere, debate has raged over the accuracy of the readings showing methane, which on Earth is produced by simple lifeforms.

Because dissipates relatively quickly—within around 12 years on Earth—and due to the difficulty of observing Mars' atmosphere, many scientists questioned previous studies that relied on a single data set.

Now an international team of experts have compared observations from two separate spacecraft, taken just one day apart in 2013, to find independent proof of methane on our neighbouring planet.

Furthermore, they conducted two parallel experiments to determine the most likely source of methane on Mars to be an ice sheet east of Gale Crater—itself long assumed to be a dried up lake.

"This is very exciting and largely unexpected," Marco Giuranna, from Rome's National Astrophysics Institute, told AFP.

"Two completely independent lines of investigation pointed to the same general area of the most likely source for the methane."

Europe's Mars Express probe measured 15.5 parts per billion in the atmosphere above the Gale Crater on June 16, 2013. The presence of methane in the vicinity was confirmed by readings taken 24 hours earlier by NASA's Curiosity rover.

Using the data, Giuranna and the team divided the region around the crater into grids of 250 by 250 square kilometres.

One study then ran a million computer-modelled emissions scenarios for each section while another team studied images of the planet surface for features associated on Earth with the release of methane.

'Indicator of life'

The most likely source was a sheet of frozen methane beneath a rock formation, which the team believes periodically ejects the gas into the atmosphere.

Giuranna said that while methane is a sign of life on Earth, its presence on Mars doesn't necessarily constitute evidence of something similar on the Red Planet.

"Methane is important because it could be an indicator of microbial life," he said. "But life is not required to explain these detections because methane can be produced by abiotic processes."

"Though not a direct biosignature of life, methane can add to the habitability of martian settings, as certain types of microbes can use methane as a source of carbon and energy," he added.

Though there is no on Mars, the European Space Agency said in February its imaging equipment had shown further evidence of dried up river beds, suggesting the Red Planet may once have been home to simple organisms.

Giuranna said that further research was needed to determine the extent of the methane ice sheet near Gale Crater.

If founded to be extensive, the it contains "could support a sustained human presence" on Mars as a possible source of fuel for industrial processes and a propellant for returning manned missions to Earth, he said.

The study is reported in Nature Geoscience this week.


Explore further

Interpreting new findings of methane on Mars

More information: Independent confirmation of a methane spike on Mars and a source region east of Gale Crater, Nature Geoscience (2019). DOI: 10.1038/s41561-019-0331-9 , https://www.nature.com/articles/s41561-019-0331-9
Journal information: Nature Geoscience

© 2019 AFP

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Apr 01, 2019
Come on. Its life.

Although we have found hydrocarbons everywhere else in the solar system, we should expect to find great quantities on this planet as well, suitable for fuel and energy and plastics and tires and such.

And of course this methane could be ancient biogenic fossil deposits as well, no?

Apr 01, 2019
"as a possible source of fuel for industrial processes and a propellant" hate to break it to them, but methane combustion requires Oxygen and is pretty much useless on Mars. Am I missing something?

Apr 01, 2019
"as a possible source of fuel for industrial processes and a propellant" hate to break it to them, but methane combustion requires Oxygen and is pretty much useless on Mars. Am I missing something?
Yeah. All the H2O and CO2 as well as all the other potential chemistry that can produce useful energy from hydrocarbons. Even if we made it from scratch.

"Liquid methane could be used as the fuel, produced from carbon dioxide and water found on Mars. Water could also be used to extract oxygen, which would be used for the oxidiser.

"In a Nasa study published in April 2016, van Susante and colleagues scoped-out how to get water and use it on Mars. As part of that study, they found several candidate resources: "garden variety" regolith, hydrated minerals, and buried ice in the form of old glaciers."

Apr 01, 2019
"is" this a sign of Life?
or
"was" it a sign of Life"?

All the petroleum pumped & coal mined, today
were deposited how long ago in the Earth's history?
How old are the Methane deposits under the Arctic Ocean?

& if it is determined that methane deposits discovered today on Mars are ancient remains of cthonic Mars Life?

Should not discourage the effort to discover if there may be more recent events,

Perhaps Mars Life?
Perhaps not?
Perhaps some other non-organic chemistry?

Apr 01, 2019
The excitement is clearly over the possibility of there being or having been life on Mars. However, the researcher is keeping it in check by saying there might be another abiotic source. So hold your horses and take a deep breath.

Apr 01, 2019
Meanwhile, on Mars, a little green dude, who goes by Fizzler, is having a hard time for revealing their position.

Apr 01, 2019
I have a hard time understand how methane could be frozen into ice in significant amounts without being biotically produced in the now dried out lake. The episodic methane produced in impacts would be very dilute if taken up by the lake water, while life could produce it continously throughout the lake.

"as a possible source of fuel for industrial processes and a propellant" hate to break it to them, but methane combustion requires Oxygen and is pretty much useless on Mars. Am I missing something?


SpaceX plans to produce rocket propellant/habitat fuel CH4 and O2 from atmospheric CO2 and surface or rock H2O and [in their case solar] power, precisely as abiotic or biotic processes does it: CO2 + 2H2O -> CH4 + O2. They will use the Sabatier process, but would be interested in ready made CH4.

Apr 01, 2019
We need to measure the isotopic ratios;

The relative abundances of resolved 12CH2D2 and 13CH3D and mechanisms controlling isotopic bond ordering in abiotic and biotic methane gases
Young, E. D. et al.
https://ora.ox.ac...+article

Apr 01, 2019
I have a hard time understand how methane could be frozen into ice in significant amounts without being biotically produced in the now dried out lake
Hydrocarbons are everywhere.

"Originally thought to occur only in the outer regions of the Solar System... significant deposits of methane clathrate have been found under sediments on the ocean floors of the Earth.

"methane is common in the solar system. Methane is what makes the atmospheres of Uranus and Neptune blue. Methane is in Pluto's atmosphere, and it's frozen to the surface of other big Kuiper belt objects like Eris and Makemake"

"Mercury holds at least 100 billion tons of water ice as well as organic material in permanently shadowed craters at its north pole... The organic material is likely made of hydrocarbons like methane and ethane, commonly found in comets and asteroids."

-The question is, if abiotic methane is everywhere else, why do we assume earths methane is biogenic?

Apr 01, 2019
And if mars methane is in clathrate form ie already combined with water it may make conversion into useful materials that much easier.

From an abstract of a paper I cant access:

"[Gas hydrates] also have a few specialized beneficial applications, and they have potential for use in a number of other areas."

-Transport in solid form rather than gas or liquid may also be a benefit.

Apr 01, 2019
"as a possible source of fuel for industrial processes and a propellant" hate to break it to them, but methane combustion requires Oxygen and is pretty much useless on Mars. Am I missing something?

Not just methane, all chemical fuels require oxygen. Oxygen can be extracted from water or CO2 on Mars. Lately it has become quite efficient to reduce CO2 to CO (carbon monoxide) and extract the oxygen (CO can also be used to make synthetic methane, but that requires hydrogen). It is much more difficult and inefficient to completely split CO2 to carbon and oxygen, so the double oxygen per molecule of CO2 is not really worth it.

Assuming the methane was limited or difficult to access, one idea would be to make extra synthetic methane by reacting CO from CO2 with hydrogen from water, assuming you could spare the water. Otherwise you keep the water, use natural methane, burn it in oxygen derived from CO2 and throw away the CO.

Apr 02, 2019
Come on. Its life.

Although we have found hydrocarbons everywhere else in the solar system, we should expect to find great quantities on this planet as well, suitable for fuel and energy and plastics and tires and such.

And of course this methane could be ancient biogenic fossil deposits as well, no?
says Spooky

No. You are still imagining that Mars is similar to Earth. Keep dreaming pussytard.

Apr 02, 2019
Meanwhile, on Mars, a little green dude, who goes by Fizzler, is having a hard time for revealing their position.
On the other side of Mars a little furry monkey called antigoracle jumping about the martian rocks wondering what happened to all the trees he used to swing in.

Apr 02, 2019
... clathrate ...

-The question is, if abiotic methane is everywhere else, why do we assume earths methane is biogenic?


Clathrates only form and remain stable at high pressures deep in Earth's ocean, both of which are sorely lacking (ocean, high pressures in the outer crust) on Mars.

We do know that Earth's methane is mostly biotic, since we can observe source volumes.

But I have now read the paper. Medusa Fossae is the Olympus Mons downwind deposit region with lots of volatiles and is likely the fragile source region for the global martian dust deposits [ https://www.ncbi....6054634/ ]. So nothing surprising with massive amounts of abiotic methane.

Still, it may hard to get methane in ice without some sort of biotic dilution process - the paper suggests long lived ice and migrating methane inside faults as one mechanism but that needs more data at a guess.

Apr 02, 2019
Yeah. Let me repeat my ref.

"Originally thought to occur only in the outer regions of the Solar System, where temperatures are low and water ice is common, significant deposits of methane clathrate have been found under sediments on the ocean floors of the Earth.[2]"

and

"Methane was formed in the interstellar medium prior to having been embedded in the protosolar nebula gas phase. This molecule was subsequently trapped in clathrates that formed from crystalline water ice during the cooling of the disk and incorporated in this form into the building blocks of comets, icy bodies, and giant planets."

-But yes, they do form under bodies of water.

"most likely source of methane on Mars to be an ice sheet east of Gale Crater—itself long assumed to be a dried up lake."
hard to get methane in ice without some sort of biotic dilution process
Uh not according to science.

Apr 02, 2019
And finally

"Methane clathrates on Mars. ... It has already been established that methane is present on Mars. H2O is also known to exist on Mars. The residual polar caps that persist after the seasonal sublimation of solid CO2 have been shown to contain either water ice or H2O in clathrate form (Kargel and Lunine, 1998)."

and also finally

"The possibility of martian methane clathrate deposits is established, and initial sources for the sequestered methane are discussed. Based on correlated data and information from disparate sources, we conclude that subsurface methane clathrate deposits are a possible immediate source for the observed atmospheric methane on Mars."

Shit torbo I thought you were above making stuff up.

Apr 02, 2019
You know, like this freak.
says Spooky

No. You are still imagining that Mars is similar to Earth. Keep dreaming pussytard.

Apr 04, 2019
This Tenuous Methane

What to do
on a planet
with at at best a tenuous atmosphere
where from 4.5billion years of dried up Martian regolith
where
humans see pictures in the cracks in their plaster ceilings
where
the very same humans
see
4.5billion years dried up Martian regolith as dried up river beds
where now this molecularly tenuous methane is seeping
as tenuously as this Martian atmosphere
what
on Mars are we going to do
how are we going to capture it
how are we going to store it
on a planet
365 days from home
with
no electricity
no materials
no food
no fuel
as
if we ever manage to actually stand on this Martian planet
it
is only to say
Here we stand and here we stay for their is our coffin
as
when this Martian sunset sets
here we die
because
our
rocket has no fuel, we have no food and no supplies
as
the little we have
will last no more than a few days
As our next launch widow back to planet Earth is another 365 days away!

Apr 07, 2019
Shit torbo I thought you were above making stuff up.


Where did I make stuff up? I don't deny that the polar ice caps has sufficient pressure to make clathrates, say. And I fail to see the significance of ice beyond the snow line much further out than Mars is or was, it has its own climate and volatiles subjected to it.

But that is far away from the local more equatorial and surface leaking source here, which I was discussing. The paper itself does not suggest clathrates.

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