Researchers call for rethinking efforts to prevent interplanetary contamination

Jun 27, 2013
Mars. Image: NASA

Two Washington State University researchers say environmental restrictions have become unnecessarily restrictive and expensive—on Mars.

Writing in the journal Nature Geoscience, astrobiologists Alberto Fairén of Cornell University and Dirk Schulze-Makuch of Washington State University say the NASA Office of Planetary Protection's "detailed and expensive" efforts to keep Earth microorganisms off Mars are making missions to search for life on the red planet "unviable."

The researchers claim "the protocols and policies of Planetary Protection are unnecessarily restricting Mars exploration and need to be revised."

The Office of Planetary Protection is like an interplanetary Environmental Protection Agency, with a mission "to minimize the biological contamination that may result from exploring the solar system."

As far as Mars is concerned, say Fairén and Schulze-Makuch, such efforts are probably in vain, as "Earth life has most likely already been transferred to Mars." Meteorite impacts have had 3.8 billion years to spread Earth life forms to Mars, as could several spacecraft that visited the planet without undergoing sterilization procedures now in place.

If organisms transferred to Mars over the failed to survive, modern organisms would likely face the same fate. On the other hand, if they did survive, say Fairén and Schulze-Makuch, "it is too late to protect Mars from , and we can safely relax the planetary protection policies."

The researchers say spacecraft looking for life on Mars should still be cleaned to some extent to avoid confusing possible Martian organisms with organisms brought from Earth. But sterilization for other missions, like orbiters and geology-oriented explorers, could be scaled back.

"As faces drastic globally," they say, "it is critical to avoid unnecessary expenses and reroute the limited taxpayers' money to missions that can have the greatest impact on planetary exploration."

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User comments : 14

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Irukanji
2.7 / 5 (10) Jun 27, 2013
Why don't we deliberately "contaminate" Mars?
gmurphy
4 / 5 (4) Jun 27, 2013
@Irukanji, because if life manifested on Mars independently, it could contain a treasure trove of information on the necessary ingredients to kick start life
Fisty_McBeefpunch
2 / 5 (8) Jun 27, 2013
I would like to see tardigrades or other extremophiles studied on Mars.
aennen
4 / 5 (3) Jun 27, 2013
Frankly we should be terra forming mars now.
Maggnus
5 / 5 (2) Jun 27, 2013
While it is very unlikely anything from Earth would survive on Mars, the probability is something more than zero. Having said that, I still think, so what. Eventually earth organisms are going to go to Mars, and the exorbitant cost of completely sterilizing larger and larger payloads going there is a wasted effort.
antigoracle
2.1 / 5 (8) Jun 27, 2013
The probability is also something more than zero that we find Martian life only to discover that they were destroyed by human contamination.
Maggnus
5 / 5 (3) Jun 27, 2013
That's a fair comment, and I would hate to see that there was life and we caused its extinction. Having said that, if there is life on mars, it probably has a better chance of fending off any earthly organisms then the Earth organisms would have of taking over from them. Their home and all.

Personally though, unless something jumps out soon to say hi, I think it is inevitable that some contamination from Earth will find a way to survive there.
Sinister1811
2.7 / 5 (7) Jun 28, 2013
Why don't we deliberately "contaminate" Mars?


At the moment, they're trying to figure out if life exists, or has ever existed there. Any contamination would bring up false positives. But if they don't find anything, it'd be interesting to bring life from Earth.
Chromodynamix
2.7 / 5 (7) Jun 28, 2013
I say, Terraform!
antialias_physorg
3.4 / 5 (5) Jun 28, 2013
efforts to keep Earth microorganisms off Mars are making missions to search for life on the red planet "unviable."

Not sterilizing them seems like a recipie for "false positives" to me.

I say, Terraform!

Erm..we're not even capable of keeping friggin' Terra habitable. Why do you think we could 'terraform' another planet into a paradise? (Espcially since no amount of terraforming will give Mars a breathable atmosphere with the right composition AND density for human life.)

Two Washington State University researchers say environmental restrictions have become unnecessarily restrictive

Drill baby, drill?
jsdarkdestruction
3.8 / 5 (4) Jun 29, 2013
"On the other hand, if they did survive, say Fairén and Schulze-Makuch, "it is too late to protect Mars from terrestrial life, and we can safely relax the planetary protection policies."

ok, lets say life was transferred from earth to mars at some point. how do we know when that was? if we introduce new organisms it could very well effect how earlier arriving former earth life has evolved on mars in the meantime and then we lose the learning opportunities the system had before being contaminated by newer earth life.
antialias_physorg
3.4 / 5 (5) Jun 29, 2013
ok, lets say life was transferred from earth to mars at some point. how do we know when that was?

I guess their argument isn't so much that life from Earth exists on Mars anyhow but that we don't see a lush landscape there. So any life that has arrived there over the past billions of years wasn't viable under Mars conditions (and so we don't need to sterilize).

I don't think I agree with that line of thought.

Especially since a transfer from Mars to Earth is a LOT more probable than the other way around because:
1: Getting stuff off of the surface of Mars is much easier than getting it off of the surface of Earth (5km/s vs. 11km/s escape velocity).
2: Earth is deeper in the gravity well of the sun than Mars is. It's more likely for stuff from Mars to lose momentum or be on an eccentric orbit and fall in than for stuff to getting a speed boost somehow from Earth orbit and get flung out.
Humpty
1 / 5 (6) Jul 01, 2013
It's only a matter of time before Phobos crash lands on the surface anyway.

Then all will be lost big time.

"Ohhh no the ancient remains rusty crap buried under mountains of dust, from the great Marrs landing 5 million years ago, will be destroyed... "
antialias_physorg
3 / 5 (2) Jul 01, 2013
Phobos is expected to break up and from a ring before impacting on Mars.

Even if it does stay intact: Then it'll take a hunderd milliom years befor itimpacts. So nothing to worry about.
(Tschebycheff analysis says that humanity will be extinct long before that with a better than 95% probability)