Mars Exchange
Planetary Protection: Keeping Mars safe for Martians

Planetary Protection: Keeping Mars safe for Martians

by Vince on Wednesday, 13th July 2016 in Expert Opinions, People, John Rummel

Dr. John D. Rummel, an adviser to Mars One, is a Senior Scientist with the SETI Institute and was formerly the Director of East Carolina University’s (ECU’s) Institute for Coastal Science and Policy. He has served twice with NASA—from 1986 to 1993 as (among other things) Exobiology Program Manager and Manager, Life Support Systems Integration, and from 1998 to 2006 as NASA’s Planetary Protection Officer. From 2006 to 2008 he was NASA’s Senior Scientist for Astrobiology, responsible for all of NASA’s efforts in astrobiology. He chaired The International Council for Science’s Committee on Space Research (COSPAR) Panel on Planetary Protection from 1999 to 2014, and is also a member of COSPAR’s Panel on Exploration and the representative of the International Union of Biological Science on the COSPAR Council. He is the lead author of some of the newest guidelines on the exploration of Mars, “A New Analysis of Mars ‘‘Special Regions’’: Findings of the Second MEPAG Special Regions Science Analysis Group,” published in 2014 in Astrobiology.

Early this year, I spoke with Dr. Rummel about the concept of planetary protection and why we need to be especially careful about contaminating Mars as we explore and look to the possibility of settling it. In this first of three parts, we explore the concept of planetary protection.

What are the primary concerns in planetary protection and how do they apply to Mars One?

“The basic issues with regard to planetary protection and human settlement are to protect science opportunities out there and to maintain the environment so that you can actually learn the lessons that you came to learn. Additionally, we need to protect the Earth against inadvertent dangers that might be present.

For Mars One, this means we need to make sure the human colony is protected against contamination of the resources it would like to depend on, as well as contamination that would thwart the science that they’re there to conduct. It also means we need to protect the colony—the people themselves—from inadvertently discovered difficulties with the Martian environment.

We don’t know if there are Martian microbes. But if there are, we don’t want to blunder into them. We want to find out what lessons we can learn from them. Also, we will be taking our own microbes with us, and we want to be sure that those terrestrial microbes don’t misbehave in the Martian environment and keep us from being able to use Mars for future human expansion.

In terms of planetary protection, this means we want to avoid forward contamination and backward contamination. So, we want to prevent forward contamination, in which we take Earth microbes places where they can cause trouble, such as making Martian resources unavailable; reproducing in such a way that you can’t determine if there were pre-existing Mars organisms there; or in fact wiping out Mars organisms before we’re able to detect them.

We also want to avoid backward contamination—bringing microbes from Mars back into our habitat or even back to Earth where they can do damage we can’t control.”

How might forward and backward contamination affect Earth and Mars?

"If you are going to have biospheres that collide, then you want to know as much about that as possible and make sure that they don’t intersect in what turns out to be negative ways. We can see this in lots of islands around the world where, either inadvertently or intentionally, people have introduced species from elsewhere. These species changed the island environment in ways that today are considered negative, though at the time they were introduced they were considered useful.

For example, back in the days of Caribbean trade, the European settlers looked at some of the Caribbean islands and could not see anything to eat there. So they put goats and other animals on the islands. Pretty soon, the goats ate everything, and the verdant green island became a more arid and unfriendly environment. We also put mongooses on the islands to control snakes. Instead, they ate the birds. Or consider the prickly pear cactus. We introduced that to Australia, and it rendered farmland unproductive. There’s a long list of organisms that we’ve taken from one place to another with disastrous results.

On Mars, we want to prevent the introduction of rogue organisms where a resource might exist. One of the fascinating things about microbes is that some don’t just eat other microbes, they eat rocks, and what they leave behind may not be very good for our purposes. For example, we have bacteria on Earth that can actually cure cracks in concrete because they are so good at mineralizing materials in rock and leaving calcareous waste behind. Consider that there may be aquifers on Mars, which we’d want to use for science or as a resource, or for both. So you have the potential for one of those terrestrial microbes to get into a Martian aquifer and seal it up before you could even use the aquifer. And of course, there’s the question of whether or not there are already Martian microbes using the aquifer. You have to be careful about what you introduce.

And then of course if there were something alive on Mars, we have no idea what the interaction between that life and humans would be, or the way that life might interact with crops we wish to grow or resources we want to use. Life has evolved on Earth in a sort of co-evolutionary dance, in which life forms learn to recognize and defend against other, potentially harmful life forms.  There may not be pathogenic interaction between potential Martian life and humans or our crops, but if the immune systems of organisms haven’t seen anything like them before, their normal defense mechanisms may not be triggered. And so we could end up with microbes growing in places where they aren’t recognized as a problem, causing harm.  So, for example, even though a Mars microbe isn’t acting the way an Earth microbe or virus might in a human or plant body, it still may seek to use the resources in the Earth organism, and cause harm that way.

An example on Earth is that we have actually tailored organisms that don’t express surface proteins that are recognized by the immune system. Without those surface proteins, the immune system doesn’t recognize the organism as something to fight. In fact, we are always seeking materials that don’t engender a reaction by our immune system—as with a titanium hip replacement—because we can use those materials as spare parts.”

It’s clear that there is much to be concerned about as Mars One prepares its experimental settlement plans—for Mars, for science, for Earth, and for future Martian settlers. In the second installment of this interview, Dr. Rummel discusses the potential for finding Martian life and what this could mean for Mars One.

Story by Vincent Hyman, a writer and Mars One volunteer living in St. Paul, Minnesota, USA. 

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