Contaminating Mars

The story I’m about to tell is a work of fiction, but it could very well happen in reality one day.  If it did, it could cause an enormous scandal in the scientific community, ruin what remains of NASA’s reputation, and end the careers of anyone directly involved.


The year is 2020.  NASA’s latest Mars rover, Intrepid, has landed successfully and wheeled around a bit, proving that all its systems are functioning.  Intrepid’s predecessor, the Curiosity rover, found evidence in 2013 that life could exist on Mars, but Curiosity wasn’t equipped to test if any life forms do exist there.  Intrepid’s mission is to follow up on Curiosity’s work.

NASA engineers have equipped Intrepid with state-of-the-art biochemical research equipment.  They gave it new technology that wasn’t available when Curiosity was launched, as well as delicate, new digging tools for collecting soil samples.  Scientist carefully selected Intrepid’s landing site, putting it near what they believe is subsurface liquid water melting from one of Mars’s polar ice caps.

Intrepid begins its work, and the very first test comes back positive.  There’s bacterial life on Mars!  Scientists around the world celebrate.  The media goes crazy, and the old theory that life on Earth began on Mars is revived once again when someone notices similarities between the DNA of the Martian microbes and that of life on Earth.  In fact, the Martian bacteria seem to have a lot in common with E. coli.

But the next test shows fewer bacteria.  The one after that shows fewer still, and soon no bacteria can be found at all.  It seems the “Martian” bacteria aren’t capable of surviving on Mars.  Soon, the truth comes out.  One of those delicate digging tools was opened before it left, meaning it may have been contaminated.  Previous studies have already shown that E. coli might be able to survive in space if shielded from ultraviolet radiation.

End of story.

Currently, the United States is part of an international agreement called the Outer Space Treaty, which stipulates that any probe we send to another planet must be thoroughly decontaminated.  NASA even has a Planetary Protection Officer, Dr. Catherine Conley, in charge of making sure that we don’t introduce invasive species to alien worlds.  The point of all this is not only to protect alien ecosystems (if they exist) but to ensure that if we do discover life on another planet, we’ll know for certain that its genuine alien life and not something that stowed away on our own space vehicles.

And yet despite the Outer Space Treaty, despite NASA’s own rules and Dr. Conley’s best efforts, one of Curiosity’s digging apparatuses was opened and potentially contaminated before it left Earth in 2011.  Could any bacteria have survived the long journey to Mars?  We don’t know.  It’s possible.  So far it doesn’t seem like any harm was done, but this could be a costly mistake if it ever happens again.

The Office of Planetary Protection

I have said before that one day science fiction won’t be science fiction anymore; it will just be fiction.  To some degree, we already live in a sci-fi world.  Look at all the diseases we can now cure, or look at the International Space Station, or just look at everything our cell phones can do.  Today, we’re going to take a look at something else that may sound like science fiction but is in fact 100% real: the Office of Planetary Protection.

The Office of Planetary Protection is sort of like the Environmental Protection Agency for the Solar System.  Its job is to ensure that NASA doesn’t violate the Outer Space Treaty of 1967, which stipulates among other things that any probe sent to another planet must not contaminate that planet with Earth-born bacteria.  The point of this is not only to protect alien ecosystems (if they exist) but also to ensure that if we do discover life on another planet, we can be certain it’s genuine alien life and not something that stowed away on one of our own space vehicles.

Take Mars as an example.  While it’s clear there isn’t anything like deer or grizzly bears on Mars, or even anything as small as a mouse or insect, there could be native Martian bacteria.  These microscopic organisms might live in areas like Newton Crater, where scientists have observed what appears to be liquid water seeping through the soil.  This water might be enough to support an entire ecosystem of microorganisms.

The Planetary Protection Office has another job as well: protecting us from any life forms that might threaten our own ecosystem.  Many nations, including the United States, are planning “sample return missions,” meaning they want to send a spacecraft to another world, have it collect samples, and send those samples back to Earth for further analysis in a laboratory.  Obviously we want to avoid an outbreak of alien bacteria similar to what happened in Michael Crichton’s The Andromeda Strain.  The Planetary Protection Office will make sure that doesn’t happen.

But just as the EPA is the source of a lot of controversy, so too is the Office of Planetary Protection.  Some scientists complain that planetary protection rules are making space exploration prohibitively expensive.  Sending a probe to Mars is costly enough without having to pay so much extra to sterilize every single delicate, mechanical component.  Given the current state of the economy and the current state of NASA’s budget, some say we shouldn’t waste money protecting alien ecosystems that might not even exist.  There are also questions about how effective the Planetary Protection Office really is given the fact that some of the Curiosity rover’s tools may have been contaminated before its launch in 2011.

Dr. Catharine Conley, the person currently in charge of NASA’s Planetary Protection Office, at least has a sense of humor about her work.  She owns a pair of Ray-Ban sunglasses, just like Will Smith from Men in Black.  She got them as a gift her first day on the job.  Despite the controversies, I feel safer knowing she’s there, keeping planet Earth safe from alien bacteria and keeping the alien bacteria safe from us.