I would like to offer an opinion about a rather controversial matter of ethics. As I say this, I keep thinking of what the general public labels as being “controversial” nowadays and I am tempted to take my word back on that. Somehow the questions on the future of humanity seem boring to most. Still, here goes:
If we ever find life on Mars, in any form, do we ethically have the right to take the planet for us (colonize)? Should we not leave it for the Martians (let them evolve, without interrupting)?
Us and Them
I started thinking about this for the first time when I saw one of the episodes of Cosmos. I am a great supporter of Carl Sagan, and while it is a privilege even to be in the same field of science as him, I must disagree on this one.
Even in the 80s, after the Viking missions, it was clear that there was no hope of finding intelligent life on the red planet. The photos sent from the surface of our neighbor were bleak and desolate. Looking for aliens hiding behind the rocks and dunes can be safely labeled chasing of shadows. While, understandably, the public was disappointed from the result (and quickly forgot about the exploration of Mars, which of course, came with a rapid decrease of financial backing, continuing till now), for many scientists it was just a call to step up search efforts. Astrobiologists, Sagan included, knew that there was still the chance of microbial life existing there, as was suggested in the community far before the Viking pictures were wired back home.
As of 2011, there is little evidence to support claims of martian life. Of course, there were some controversial findings, most notably a meteorite recovered in the Antarctic in the 90s, but no safe conclusions can be drawn on their exact nature. Still, the view among astrobiologists is that the absence of evidence cannot, and should not, be considered evidence of absence. It is obvious to anyone with a proper educational background that the search for life which is executed at a planetary scale might take a rather long time. The martians can be hiding behind any of those rocks, and there might be a whole ecosystem just below the surface.
But let’s get back on the original question. What should we do if (and some believe we will, rather soon) martian microbes are found indeed?
By looking at our own tumultuous history, especially the introduction of foreign species to isolated islands, the effects of the arrival of Man are detrimental to the local ecosystem, to say the least. It is very possible that even in this moment there is life on Mars, but it’s terrestrial. B. subtilis spores are not the only microbes capable of surviving the trip and landing on Mars. I have wrote about planetary protection on many occasions and will be the first to stress its importance. Preserving the integrity of any extraterrestrial ecosystem is of paramount importance.
But still, should we not colonize? Leave the only other world in our Solar System which has some degree of habitation by humans? What are the other options? Should we go to the Moon, where there is almost no water (there is water ice on Mars), or Venus, where the temperatures at the surface measure in the hundreds of degrees Celsius? All that is left after these choices are the gas giants and a few satellites. Oh, and quite a lot of asteroids. Hell, in the next century everyone will have a home on one of the asteroids in the rings of Saturn.
While life might be common, there are many reasons to believe that intelligence is not (it is appropriate that there are two variables in the Drake equation for each one), and it might take forever (if possible at all) for it to evolve from simpler life. We should make the preservation and study of alien life our priority when moving further out in our system, even if this means we should stay back for a few decades in order to achieve the necessary levels of technology and knowledge to accomplish this, with contamination risks at minimum. But we should not take our civilization for granted. We really might be the only ones around, and we should take every chance for our expansion, prosperity and further evolution.