How do we keep our bacteria to ourselves? [Image by NASA]
There's a possibility that Mars was once—or still is—home to microbial life. With this in mind, the Committee on Space Research (COSPAR) drew up a plan detailing Mars's Special Regions. These regions are areas on the planet where no human, machine, or robot can go. By making certain regions off-limits, there's less of chance that microbes can contaminate these sites.
A contamination can lead to false discoveries in the future. Imagine hearing an announcement that NASA has finally found life on Mars, only to find that the so-called alien life is in fact just microbial hitchhikers from Earth. Bringing earthly microbes to outer space can also have some unexpected consequences.
One basic guiding principle in the search for alien life is that where there's water, there's a possibility that there's also life. Mars, long thought to be dry and barren, turned to have traces of water both underground and on the surface.
Spacecraft would need to avoid landing in Special Regions. [Photo by NASA]
This means that there may actually be Martians, living or long dead, but they probably aren't multiple-legged green aliens that are hell-bent on invading Earth. They're likely to be microorganisms, and they're likely to be found in certain parts of the planet.
These are the Special Regions—parts of Mars that can't be contaminated because they may contain signs of alien life. The regions in the list have water ice within five meters below the surface. Unfortunately, it's somewhat impossible to search for signs of alien life from afar. NASA can send a rover to a particular spot and search for signs of life there.
Seems simple, doesn't it? Well, perhaps not as simple as all that. As mentioned above, if we're careless and a rover detects signs of life, it may be that what the rover's detecting is actually a microbe from Earth. Of course, people that handle Mars rovers make sure to clean the machines thoroughly before sending them off to their missions. However, present sterilization techniques may not be enough to ensure that there will be no tiny hitchhikers tagging along for a trip to Mars.
So what should be done before we send rovers to Mars's Special Regions?
Space craft like the Curiosity Rover may be able to sniff out life on Mars. [Image by NASA]
“If we found a Special Region on Mars, certainly you’d want to have kind of a hands-off zone until we fully understood it,” said John Rummel, one of the authors of a paper that redefined what the Special Regions are. Thus, it's important prohibit spacecraft from entering a Special Region without due information. Spacecraft would also have to go through some pretty intense sterilization measures before they can go to the regions.
The COSPAR Planetary Protection Policy lays out the sterilization requirements quite well. More importantly, even private institutions that want to send a rover to Mars would need to abide by these requirements. If Elon Musk's company SpaceX, for example, wants to send a rover to Mars, the company would have to seek approval from the government and make sure that the vehicle properly sterilized. This way, we don't need to worry about Earth microbes contaminating Mars's Special Regions.
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