The overprotection of Mars?

The overprotection of Mars?
This self-portrait of NASA's Mars Curiosity Rover includes a sweeping panoramic view of its location in the Yellowknife Bay region of Gale Crater. The mosaic was constructed using frames from the rover's Mars Hand Lens Imager (MAHLI) and Mastcam. Credit: NASA, JPL-Caltech, MSSS - Panorama by Andrew Bodrov

A recent commentary paper published in the journal Nature Geoscience argues that planetary protection policies and practices designed to guard solar system bodies from biological contamination from spacecraft need to be re-evaluated because they are "unnecessarily inhibiting" a more ambitious agenda to search for life on Mars.

In the paper, called The Overprotection of Mars, co-authors Alberto G. Fairén of the Department of Astronomy, Cornell University and Dirk Schulze-Makuch of the School of the Environment, Washington State University, also argue that, from an astrobiological perspective, the most interesting missions to "Special Regions" - where, in theory, Mars could exist or Earth life could survive - are rendered "unviable" as a result of onerous Committee on Space Research (COSPAR) protocols and the need to comply with "detailed and expensive sterilization requirements."

For Fairén, the key point of the paper is that, if life can be transferred to Mars in our spacecraft, then the transfer can also happen "naturally, with or without our spacecraft" - and that most likely it "has already happened."

"If Earth life cannot thrive on Mars, we don't need any special cleaning protocol for our spacecraft; and if Earth life actually can survive on Mars, it most likely already does, after four billion years of meteoritic transport and four decades of spacecraft investigations not always following sterilization procedures," he says.

"Planetary protection policies are at least partly responsible for the lack of life-hunting Mars missions since Viking, as they impose very stringent requirements for sterilization of the spacecrafts which, in my opinion, are not necessary," he adds.

A Bug in the Program

In Fairén's view, one of the main shortcomings of current planetary protection policies is that "no spacecraft is treated entirely" - including, for example, some pieces intended to burn in the Martian atmosphere, as well as the launching system - but the "actual" hardware touching down on the surface of Mars is in contact with these other "dirty" parts for several months

"This has happened in all Mars missions. Absolute sterilization does not exist, even treated spacecrafts carry hundreds of thousands of bugs. This has also happened in all Mars missions," he says.

"The best sterilization procedure is the exposure of the spacecrafts to solar and cosmic radiation during the trip and once on the surface of Mars," he adds.

According to Fairén, we already "know for sure that bugs from Earth vessels have landed on Mars" - and he firmly believes that all existing sterilization procedures will be "outdated the second we send a human to Mars."

The overprotection of Mars?
A test operator in clean-room garb observes rolling of the wheels during the first drive test of NASA's Curiosity rover. Credit: NASA / JPL-Caltech

"NASA's program of human exploration of the Solar System includes sending humans to Mars in the 2030's, and it won't be a surprise if other nations also try to put a human on Mars even earlier. You can't sterilize humans, and as soon as an astronaut steps on Mars, you will have Earth bacteria on Mars. Are all these complicated procedures valid just for the next two decades? What happens next?" he says.

The Search for Extant Life

Fairén also says that existing policies hinder the search for extant life on Mars because of the "costs in time and money associated with the cleaning." One example he cites is that of the Viking mission, which he says devoted over 10% of its one billion dollar budget to planetary protection measures.

"We are talking about over $100 million. You can do a lot of science with that amount of money. And we cannot forget that, if our target is a 'Special Region' of Mars where life can potentially exist, then the required protocols are even more stringent. [The] bottom line is that a thorough cleaning of a spacecraft aimed [at the] in situ search for life on a special region of Mars today would cost a lot of money and effort," he says.

Even if the complete sterilization of a spacecraft "cost only $1 million," Fairén still questions the sense of spending it, and expending 'a lot of effort' on something that he stresses is "not necessary."

"Of course, if sterilization was actually necessary the cost doesn't matter, you'd have to do it. If biological contamination of Mars with spacecraft would actually be a risk [there would be] no more to say, you'd have to sterilize whatever the cost, period. But our point is that such risk does not exist - and that's what we explain in the commentary," he says.

Looking ahead, Fairén argues that planetary protection policies "should be scaled down" - with only one exception: if a mission is "specifically targeted" to the search for life, he believes that sterilization "to some extent" could be in order - primarily to avoid the possibility of discovering what he calls "false positives."

"If we find life on Mars, we need to be sure that the life we are seeing did not come onboard the same spacecraft looking for it. And that's a complicated problem," he says.

Appropriate Protection of Mars

The following issue of Nature Geoscience features an article outlining a strong rebuttal to the commentary paper - written by Catharine A. Conley, the NASA Planetary Protection Officer with the Science Mission Directorate at NASA Headquarters, and John D. Rummel, a professor of biology at East Carolina University. Rummel is the current Chair of the COSPAR Panel on Planetary Protection and in previous years was the NASA Senior Scientist for Astrobiology and NASA's Planetary Protection Officer.

The overprotection of Mars?
Lockheed Martin Space Systems technicians Jim Young (left) and Jack Farmerie (right) work on the science deck of NASA's Phoenix Mars Lander. The spacecraft was built in a clean room under NASA’s planetary protection guidelines to prevent microbial life from being transported to Mars. Credit: NASA /JPL/UA/Lockheed Martin

In the article, called Appropriate Protection of Mars, the authors state that efforts to limit spacecraft contamination "are already continuously scrutinized in light of the latest science developments, represent the consensus of the international scientific community, and are essential for any valid plan to search for any extant or extinct life on Mars."

Moreover, the authors also contend that the premise that planetary protection is too expensive "only pertains if the objectives aren't worth the cost" - adding that they "believe that the investment is not only worth it, but essential. Preventing the contamination of the Mars environment is the best way to ensure we have a chance to understand our own origins and the potential for life on Mars, now and in the future."

"I completely disagree with the paper, both because of the errors present in logic and because of the strawman planetary provisions that they posit for 'specific recommendations for the elimination or reduction of these protocols,' [which] are almost the same as the provisions currently in place," says Rummel.

"Note that they do not elaborate the benefits to be gained for astrobiology by going to regions that can grow Earth organisms, and then introducing Earth organisms into them," he adds.

In Rummel's view, astrobiology gains from the current planetary protection policies because those policies are focused - in the "forward contamination" direction - on preserving the conditions on Mars, and other bodies, so that scientists and researchers "don't end up studying their own contamination when searching for extraterrestrial life." Without such policies, he argues that we would lose the opportunity to study life, or the lack of it, on Mars.

"They [the current planetary protection policies] only hinder the search for human-associated contamination and the potential to contaminate resources that we may one day wish to use on Mars. I don't think that that is a problem," he says.

"Every aspect of planetary protection that might 'hinder' the search for extant life elsewhere, and protect Mars resources from Earth contamination, can be solved by engineering we already know how to do - witness the Viking missions launched in 1975. So I would recommend continued investment in the technology to make that engineering less expensive and more effective, and make [the policies] expected practice rather than done by exception - as with the Mars Science Laboratory," he adds.

Explore further

Researchers call for rethinking efforts to prevent interplanetary contamination

More information: "The overprotection of Mars." Alberto G. Fairén, Dirk Schulze-Makuch. Nature Geoscience 6, 510–511 (2013) DOI: 10.1038/ngeo1866
Published online 27 June 2013
Journal information: Nature Geoscience

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Citation: The overprotection of Mars? (2013, November 19) retrieved 17 July 2019 from
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Nov 19, 2013
Well, finally, an explanation as to why probes are not sent to the really suggestive areas of Mars, places where photos indicate there may already exist alien life forms. It makes sense to avoid contamination, except when one recognizes that such contamination has already taken place either naturally or via spacecraft already sent to Mars. So I concur - go ahead and land probes in the most biologically interesting areas of Mars and let's see what's growing there!

Nov 19, 2013
Any native Martian life would be much better able to survive there than earth life. If it found earth life edible it would make short work of it, including us.

But since we will eventually be colonizing mars it is vital to know how earth life will fare there. And so contaminated landing sites should be thoroughly examined, and perhaps higher lifeform experiments should somehow be conducted first, before humans land there.

Iran sends monkeys into orbit. Perhaps they will want to try this.

Nov 19, 2013
common sense prevails at last. any grouping of microbes native to mars would not be of ANY enduring interest if they could not be distinguished from small baseloads of microbes brought from earth after standard sterilization.

if we contaminate mars with just a small amount of bacteria, it really shouldn't make a difference. and if it does, because the level of martian microbes that can be detected is so small as to be hard to distinguish from the native microbes we bring with us-------------then native martian life cannot be that substantial to begin with. if its that insubstantial and rare to find, than its not that interesting.

Nov 19, 2013
COSPAR's protocols were invented before astrobiology became a science, because of social concerns of risk and moral. This is a question between having money for research or satisfying public outreach and moral responsibility.

I have long argued that transpermia after a biosphere is established is very low likelihood. And if we transport modern life elsewhere, it is easy to establish its divergence time. NASAs problem is that they want to announce exolife as early as they can, ironically because they lack a steady astrobiology funding.

So I think the new paper is important. Hopefully it will start a discussion on where the money should go.

@LariAnn: Landing places on Mars are mostly restricted by the difficulties of landing. Current systems need a deep atmosphere, you can notice that crafts lands in areas a few km below the datum.

There are no photos or any other accepted observation indicating that " there may already exist alien life forms". Which is why you give no references.

Nov 19, 2013
Maybe little green men might spy on our equipment and make their own.......REALLY!!?? Any native Martians will have distinctive DNA. There IS supposition that earth life arrived on Mars courteous of the Chixculub event blasting enough debris into space that a virtual statistical certainty exists that Mars and other bodies tasted some of our life, bugs, plants, etc., so if our first astronauts get chased by a Martian T-Rex then we only have our own mother earth to blame. Seriously, true Martian life, even ancient immigrant life, will have its own DNA. These planetary protection protocols went into effect before we could test DNA and use the results. That makes the protocols obsolete, and since humanity of one nation or another IS gonna go there anyway then there is a good chance that our 'protocols' will not be followed by the Chinese, Iranians, Brazilians, etc. So ditch the protocols and full speed ahead lest we lose out....'nice guys' finish LAST!

Nov 19, 2013
Even if we transported 100 tons of nothing but the most contaminating Earth organisms around, the impact on Mars and any potential life would go unnoticed for centuries.

The fear that Earth organisms would act like invasives on Earth is utter idiocy. Invasives thrive due to lack of competition in an IDEAL environment.

There is no place on Mars that would be considered ideal for any Earth organism. It would be considered on the edge of survivability for even the hardiest Earth organism, and even if it had the planet to itself it'd still take many human lifetimes before it spread far beyond the touchdown site.

Now that I know this is the policy they follow I have lost all interest in planetary exploration. It is an utter waste of money time due to a paranoid fear of Earthly contamination.

If we'd been serious about finding life, we'd have looked at the mud volcano fields there or the deepest part of the Hellas Basin.

Instead every mission was designed to fail, what an outrage.

Nov 19, 2013
Instead every mission was designed to fail, what an outrage.

"Designed to fail" is the American way. It is caused by Capitalism. If you want to make money, you don't make money by selling someone a perfect product, you make money by selling someone a product that is only just good enough to convince everyone it was worth it, before it breaks, so that they come back for the next version.

Same deal with NASA. If those engineers completed their "missions" they'd all be out of jobs. They don't want that, obviously, so you keep designing missions who's only purpose is to promote the next mission.

Nov 20, 2013
Whats up with the rating bots voting down everything.

Nov 20, 2013
I would say that I agree with the authors. Field work on Mars is no different than field work here, and there are established protocols for collecting samples and working in pristine environments. As pointed out in the story, there's no practical way to completely eliminate contamination of a site in the field, no matter whether you're on Mars or here on Earth. Methods established in the past 100 years, since the introduction of the field of microbiology, should provide an adequate amount of protection of the Martian environment for scientific purposes.

The defensive tone of the response seems a bit over the top, and may be the result of someone feeling like they got their toes stepped on. I imagine they get commentary from all sides of the issue and must take the most cautious approach in order to avoid having blame directed at them. How would you like to be the guy famous for allowing Mars to get contaminated forever, or something like that.

Nov 23, 2013
We should intentionally colonize Mars with all the beneficial Earth microbes we can think of.

The odds of finding fossil evidence of life are very slim when using a few dumb remote controlled robots.

The reason people find fossils and archaeological sites on Earth is because there are 7 billion of us either actively looking, or accidentally discovering them when digging a foundation for a new structure, or mining for some other material.

This suggests the best way to find any ancient remains on Mars is in fact to colonize it with as much Earth life as possible.

Nov 23, 2013
This comment has been removed by a moderator.

Nov 24, 2013
I would like to see life get introduced to Mars. I think it would give Mars that push or nudge that it needs to become habitable.

Nov 26, 2013
I agree in so much as it makes no sense to sterilize something unless you can keep it isolated from contact with anything that is unsterilized.

To do otherwise is a waste of time, energy, and money.

Nov 28, 2013
GSwift7 - there is a difference between Mars and Earth. The exobilogists want to send amazingly sensitive experiments to Mars able to detect a single amino acid in a gram of soil.

And - we don't know if there has been any transmission of life between Earth and Mars. If there has then it probably happened billions of years ago - at least that's the most likely time for it to happen.

It is possible for Earth life to outcompete Mars life. Just like, e.g. rabbits are not particularly adapted to Australia, but the marsupials never developed placental birth, which turns out to be superior. microbial lifeon Earth with its rich ecosystem must have explored many avenues never explored on Mars. And probably vice versa also because Mars is such a different planet from Earth. We have microbes with astonishing levels of resistance to UV and ionizing radiation and even to the low atmospheric pressure of Mars, capabilities you would think they wouldn't need on Earth but never lost it.

Nov 28, 2013
Yes is possible eventually that we could transform Mars by introducing life - but we don't yet know how to make even a self sustained space settlement never mind a planet. And studies of how to do it for Mars suggest introducing life in a particular order, e.g. the cyanobaceria first and aerobes much later - not just adding a whole bunch of microbes at random and hope it works. And Mars is very different from Earth, no continental drift, no magnetic field, far more elliptical orbit, and we don't know enough to recreate a second Earth never mind a Mars ecology able to last long term + even most optimistic ideas would take centuries and most likely millennia to terraform a planet - if we ever do find out how to do it with confidence.

Nov 28, 2013
And until then, Mars is far more inhospitable than Earth. Even after a meteorite strike like the one that lead to the extinction of the dinosaurs, Earth would be far more habitable than Mars is likely to be even after a century or more of terraforming. It's not a good reason to rush into it and lose all the understanding we could gain from studying Mars in its pristine state first. We are amazingly lucky to have a planet so like Earth in our solar system, we mustn't spoil this just for short term goals - not when we don't even know what it is we are spoiling and what things we might learn about e.g. evolution of life, biology, nanotechnology (biology is close to nanotech) etc.

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