Salts Could Be Important Piece of Martian Organic Puzzle, NASA Scientists Find


May 20, 2021

A NASA team has found that organic salts are likely present on Mars. Like shards of ancient pottery, these salts are the chemical remnants of organic compounds, such as those previously detected by NASA’s Curiosity rover. Organic compounds and salts on Mars could have formed by geologic processes or be remnants of ancient microbial life.

Besides adding more evidence to the idea that there once was organic matter on Mars, directly detecting organic salts would also support modern-day Martian habitability, given that on Earth, some organisms can use organic salts, such as oxalates and acetates, for energy.

“If we determine that there are organic salts concentrated anywhere on Mars, we’ll want to investigate those regions further, and ideally drill deeper below the surface where organic matter could be better preserved,” said James M. T. Lewis, an organic geochemist who led the research, published on March 30 in the Journal of Geophysical Research: Planets. Lewis is based at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. 

Lewis’s lab experiments and analysis of data from the Sample Analysis at Mars (SAM), a portable chemistry lab inside Curiosity’s belly, indirectly point to the presence of organic salts. But directly identifying them on Mars is hard to do with instruments like SAM, which heats Martian soil and rocks to release gases that reveal the composition of these samples. The challenge is that heating organic salts produces only simple gases that could be released by other ingredients in Martian soil.

What do you do if you have a sample from another planet, and you want to find out if it contains a certain molecule…maybe even one that will reveal whether the planet can sustain life? When scientists face a situation like this, they use an amazing tool: the mass spectrometer. It separates out materials, allowing scientists to look very closely at a sample and see what’s inside. Credits: NASA/Goddard Space Flight Center
Download video here

However, Lewis and his team propose that another Curiosity instrument that uses a different technique to peer at Martian soil, the Chemistry and Mineralogy instrument, or CheMin for short, could detect certain organic salts if they are present in sufficient amounts. So far, CheMin has not detected organic salts.

Finding organic molecules, or their organic salt remnants, is essential in NASA’s search for life on other worlds. But this is a challenging task on the surface of Mars, where billions of years of radiation have erased or broken apart organic matter. Like an archeologist digging up pieces of pottery, Curiosity collects Martian soil and rocks, which may contain tiny chunks of organic compounds, and then SAM and other instruments identify their chemical structure.

Using data that Curiosity beams down to Earth, scientists like Lewis and his team try to piece together these broken organic pieces. Their goal is to infer what type of larger molecules they may once have belonged to and what those molecules could reveal about the ancient environment and potential biology on Mars.

“We’re trying to unravel billions of years of organic chemistry,” Lewis said, “and in that organic record there could be the ultimate prize: evidence that life once existed on the Red Planet.”

While some experts have predicted for decades that ancient organic compounds are preserved on Mars, it took experiments by Curiosity’s SAM to confirm this. For example, in 2018, NASA Goddard astrobiologist Jennifer L. Eigenbrode led an international team of Curiosity mission scientists who reported the detection of myriad molecules containing an essential element of life as we know it: carbon. Scientists identify most carbon-containing molecules as “organic.”

Research scientist Dr. Jennifer Eigenbrode discusses the discovery of ancient organic molecules on Mars.
Credits: NASA’s Goddard Space Flight Center/Dan Gallagher
Download this video in HD formats from NASA Goddard’s Scientific Visualization Studio

“The fact that there’s organic matter preserved in 3-billion-year-old rocks, and we found it at the surface, is a very promising sign that we might be able to tap more information from better preserved samples below the surface,” Eigenbrode said. She worked with Lewis on this new study.

Analyzing Organic Salts in the Lab

Decades ago, scientists predicted that organic compounds on Mars could be breaking down into salts. These salts, they argued, would be more likely to persist on the Martian surface than big, complex molecules, such as the ones that are associated with the functioning of living things.

If there were organic salts present in Martian samples, Lewis and his team wanted to find out how getting heated in the SAM oven could affect what types of gases they would release. SAM works by heating samples to upwards of 1,800 degrees Fahrenheit (1,000 degrees Celsius). The heat breaks apart molecules, releasing some of them as gases. Different molecules release different gases at specific temperatures; thus, by looking at which temperatures release which gases, scientists can infer what the sample is made of. 

“When heating Martian samples, there are many interactions that can happen between minerals and organic matter that could make it more difficult to draw conclusions from our experiments, so the work we’re doing is trying to pick apart those interactions so that scientists doing analyses on Mars can use this information,” Lewis said.

Lewis analyzed a range of organic salts mixed with an inert silica powder to replicate a Martian rock. He also investigated the impact of adding perchlorates to the silica mixtures. Perchlorates are salts containing chlorine and oxygen, and they are common on Mars. Scientists have long worried that they could interfere with experiments seeking signs of organic matter.

First photo taken on Mars in 1976 by Viking 1.
This is the first photo ever taken on the surface of Mars. It was taken by NASA’s Viking 1 spacecraft just minutes after it landed on the Red Planet on July 20, 1976.Credits:
Credits: NASA/JPL More information here.

Indeed, researchers found that perchlorates did interfere with their experiments, and they pinpointed how. But they also found that the results they collected from perchlorate-containing samples better matched SAM data than when perchlorates were absent, bolstering the likelihood that organic salts are present on Mars.

Additionally, Lewis and his team reported that organic salts could be detected by Curiosity’s instrument CheMin. To determine the composition of a sample, CheMin shoots X-rays at it and measures the angle at which the X-rays are diffracted toward the detector.

Curiosity’s SAM and CheMin teams will continue to search for signals of organic salts as the rover moves into a new region on Mount Sharp in Gale Crater.

Soon, scientists will also have an opportunity to study better-preserved soil below the Martian surface. The European Space Agency’s forthcoming ExoMars rover, which is equipped to drill down to 6.5 feet, or 2 meters, will carry a Goddard instrument that will analyze the chemistry of these deeper Martian layers. NASA’s Perseverance rover doesn’t have an instrument that can detect organic salts, but the rover is collecting samples for future return to Earth, where scientists can use sophisticated lab machines to look for organic compounds.

Banner image: This look back at a dune that NASA’s Curiosity Mars rover drove across was taken by the rover’s Mast Camera (Mastcam) on Feb. 9, 2014, or the 538th Martian day, or sol, of Curiosity’s mission. For scale, the distance between the parallel wheel tracks is about 9 feet (2.7 meters). The dune is about 3 feet (1 meter) tall in the middle of its span across an opening called “Dingo Gap.” This view is looking eastward. Credits: NASA/JPL-Caltech/MSSS. More information here.

By Lonnie Shekhtman
NASA’s Goddard Space Flight Center, Greenbelt, Md.

Last Updated: May 20, 2021

Editor: Svetlana Shekhtman

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Ron Long
May 21, 2021 2:40 am

While I am happy to se NASA sending rovers to Mars, this search for life signs by mass spectrometer detection of gases that COULD signal organic compounds, and which actually INFER organic molecules, is a mixture of science and something else. When Otis Sistrunk walks up and peers into the rover camera show me the picture (Otis was the Oakland Raiders football player whom the announcers said was from the “University of Mars”).

Bill Powers
Reply to  Ron Long
May 21, 2021 4:29 am

I stopped reading this at A NASA team has found that organic salts ARE LIKELY

Joao Martins
Reply to  Bill Powers
May 21, 2021 5:08 am

You’ve done right! So did I!

“to be likely” is not science; for science (i.e., knowledge), either they are there or they are not there; “yes” or “no”: because anything (and its opposite) can be “likely”.

willem post
May 21, 2021 2:59 am

“The fact that there’s organic matter preserved in 3-billion-year-old rocks, and we found it at the surface, is a very promising sign that we might be able to tap more…”

Each pound of TAPPING will cost about $1 billion
I am so glad NASA is doing all that TAPPING in the MOON, and MARS, and WHEREVER
We should ALL be glad, that NASA folks will have job security for decades.

Is it really important to know there are microbes hidden somewhere in the universe?

oeman 50
Reply to  willem post
May 21, 2021 7:45 am

I thought organic molecules (like formaldehyde) had been discovered in deep space. So is anyone acknowledging these organics could be from an asteroid or meteor?

Jay Ayer
May 21, 2021 3:13 am

Mars is an interesting technical challenge but nothing more. With very little atmosphere and no global magnetic field Mars is hostile to life. Humans would always have to wear pressure suits and be constantly subjected to harmful cosmic radiation. We might as well be exploring and exploiting the Moon which is much closer and cheaper. In many respects there is little difference between the two environments.

If some fool in Washington wants to spend lots of our tax dollars they will talk about going to Mars. Their favorite aerospace contractor will make billions and we will have nothing to show for it except a base on the Moon that was built by China.

May 21, 2021 3:20 am

There’s a good chance China has introduced some life to the red planet; judging by their general attitude to space etiquette.

Last edited 24 days ago by fretslider
Reply to  fretslider
May 21, 2021 4:45 am

They might just leave some MSG for NASA.

Reply to  fretslider
May 21, 2021 5:09 am

There’s a good chance China has introduced some life to the red planet; judging by their general attitude to space etiquette.

In that case, there’s an excellent chance America has polluted the entire moon surface with depleted uranium and toxic consumer waste, judging by their general attitude to terrestrial etiquette.

You see how stupid Bolsheviks’ cliche’s and their racist soundbites are when they touch your own culture? You are being taught to hate, by the very people who tell me every day that you are overpopulating Their planet.
Now let them red numbers flow…

Last edited 24 days ago by paranoid goy
Reply to  paranoid goy
May 21, 2021 5:48 am

Bad news for you….China is still overpopulated despite Mao’s and WW2 killing of millions…..and the one child per family policy. China still struggles with food supply and poverty even while exploring Mars…..and sterilizing Uighurs. CCP is the new nazi party.

Reply to  Anti-griff
May 21, 2021 10:15 am

That is not overpopulation. That is poor government / economic model.
I have posted before my back-of-the-envelope calculations here.
With the corn grown in USA annually, we could annually provide one-seventh of a 2,000-caloire-per-day diet to a world population of 10 billion.

That is merely on corn from USA.
[calories per bushel x bushels per year, and 10 bn ppl x 365 days x 200 cal.]

That does not include: wheat, rice, legumes, meat, vegetables, fruit, etc., etc. and does not include any other country.

Planetarily, there is plenty of food. Look at where there is food on the shelf and where there are shortages. The problem is economy – government formula.

Adam Smith said that “the wealth of nations” is built upon Land, Labor, Capital, and Entrepreneurship. To that mantra, we need to also realize that there are a couple more ingredients. This is the economic-political context. People need to be able to own property and be largely free to enter into mutually-agreeable commercial exchange agreements (one way to phrase “capitalism” – but the problem with the term “capitalism” is that as soon as you argue a benefit of “capitalism as many of us understand it, Communists throw more stuff in there). We also need a government that supports property ownership, and supports the noted commercial agreements. This draws the money system into the mix.

And, we are headed in the wrong direction.

We from the Anglosphere, starting in 1920s, have had a sustained campaign to convince ANY country with Dark-Skinned people that “lower population is the road to economic success.”

“Reproductive Rights and Wrongs” is one of the books documenting this history. But it is far more extensive than any book can cover. A specific example of our USA desire to control population growth of people in Dark Skinned countries is the 1974 NSSM-200. It is not that long so we can all read it. On Wikipedia.

Also, in that population control era, we often had explicit ties for foreign aid for any country with Dark Skinned people: to receive the noted economic aid – grants or loans – a nation would need to meet population control plans.

While this population control strategy may work to achieve economic growth in the short term (albeit that effect is confounded with incoming foreign aid) in the short term, it does not work in the long term. Many nations are now figuring this out.

China, Japan, SK, and other places are figuring out that they have a distorted population structure, with old people needing transfer-of-wealth support outnumbering the young adults to produce wealth by working.

Reply to  paranoid goy
May 21, 2021 6:44 am

You do realise that all this woke interplanetary nonsense was dreamed up long after Apollo, right?

You are being taught to hate

Far too late for that.

Live and let live – which, I’m reliably informed, translates as live long and prosper in Vulcan.

Reply to  paranoid goy
May 21, 2021 9:57 am

I’ve always thought it kinda funny. The first thing Neil Armstrong did before climbing down the ladder and taking that historic first step. Was throw out a bag of astronaut poop.

Reply to  fretslider
May 21, 2021 6:05 am

Which components are coming from Wuhan so we can start preparing?

Reply to  fretslider
May 21, 2021 1:25 pm

Space COVID.

May 21, 2021 5:02 am

Just one question: Since there are still places where ice is sitting on the surface of Mars, is there some reason NASA hasn’t/can’t land a mechanical wandering lab there and have it drill into the ice? Mightn’t better samples of preserved organic materials be available that way?

Meantime, Gekko is chasing Willis around, looking for ways to keep her happy. Willils was a female Martian bouncer. Is there life on Mars? Ask Heinlein. It’s probably all underground, anyway.

Reply to  Sara
May 21, 2021 8:24 am

See ¨Missions¨ Part 1 and Part 2 out on BlueRay now. A step beyond the Martian Chronicles .
Interesting the Americans there used a fusion rocket, very fast transit.

Coach Springer
May 21, 2021 5:16 am

If it’s just likely, why ““The fact that there’s organic matter preserved in 3-billion-year-old rocks ….”? Two sides of the mouth at the same time seems to be a scientific talent these days.

Frank from NoVA
May 21, 2021 5:30 am

“We’re trying to unravel billions of years of organic chemistry,” Lewis said, “and in that organic record there could be the ultimate prize: evidence that life once existed on the Red Planet.”

I thought our intellectual betters had already settled this science…


Timo, not that one
Reply to  Frank from NoVA
May 21, 2021 7:51 am

This was one of Heller’s best posts ever. The best part was where he pointed out that: “Global warming finally did the Martians in.”

Tom Abbott
May 21, 2021 5:52 am

Elon Musk needs to put a biologist on Mars, and then we could settle these questions pretty fast.

Reply to  Tom Abbott
May 21, 2021 6:06 am

Is that the great tax credit mission?

May 21, 2021 6:04 am

I hear the Chinese rover actually has a rock hammer and magnifying glass. /sarc

H. D. Hoese
May 21, 2021 6:49 am

Moon may already be contaminated?
“The probe infamously included tardigrades on board that mission managers had not disclosed to the public, and the lander crashed with its passengers in tow, raising concerns about contamination….. a planetary scientist at the University of Kent, wanted to find out whether tardigrades could survive such an impact—and they wanted to conduct their experiment ethically…..The results suggest the tardigrades on Beresheet were unlikely to survive.” Discussion about panspermia follows.

May 21, 2021 9:16 am

I haven’t heard much about the rovers or its science; lot’s about the helicopter. Is the rover actually, you know, like, roving or is it stationary? If stationary, why? And why are we hearing of NASA Earth based “discoveries” of conjectures?

May 21, 2021 9:49 am

Marketing. Also, conflation of logical domains is part and parcel of modern science.

May 21, 2021 12:51 pm

Perseverance started roving on March 5.

It has been studying the rocks in vicinity of the landing site while supporting and documenting Ingenuity’s flights.

Last edited 24 days ago by David Middleton
May 21, 2021 1:24 pm

Carbonaceous chondrites, a type of meteorite, contain abundant organic compounds. These bombard Mars, and likely did so in abundance in its early history.

Tom Abbott
May 21, 2021 1:52 pm
Michael S. Kelly
May 21, 2021 5:32 pm

Douglas Fairbanks bought a mansion for his fiance, Mary Pickford, back in 1919, and their home became known as “Pickfair.” When I first encountered the term “CheMin” in this post, I thought at first that it referred to the home of Ernesto “Che” Guevara and his first wife Hilda “Minnie” Gadea.

I guess they used to give tours of Pickfair back when I lived in SoCal (before Pia Zadora bought it and demolished it), but I could never afford the tour. Instead, I got a tour of LuddWhite, the home of Allen Ludden and Betty White.

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