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Terraforming Mars: to be or not to
The Red Planet is now within mankind’s reach. It’s mysteries now slowly being unfolded by orbiting as well as surface exploration spacecraft and robots. Scientists have reached the conclusion that Mars once had life. It might still be lurking somewhere beneath the surface. But right now as far as mankind is concerned, it is not habitable for humans. We cannot take off the gloves and let the sand sift through our fingers. Should mankind be satisfied with the way things are? Just explore the planet as it is and leave things be? Or try to make another planet habitable for humans?
At an Astrobiology and Science Conference, a group of scientists, experts and even science-fiction writers got down to discuss whether “Terraforming Mars,” in other words, bringing it back to life, was possible and whether it should be done. It was co-sponsored by Nasa’s Astrobiology Magazine, Breakpoint Media and the Sci-fi Museum in Seattle. The debate took into consideration not just the technological and scientific aspects but also the social and ethical pros and cons of bringing another planet to life.
Habitability
Dr Chris McKay, planetary scientist at Nasa’s Aimes Research Centre, is in favour of bringing Mars back to life. He along with co-researcher, Dr James Kasting has been working on the idea since the 70s. His viewpoint though is slightly different than the “Terraforming” version the rest of us have. He feels that Mars should be made habitable for life, not necessarily habitable for humans.
“Human beings are a particular subset of life that require particular conditions. And it turns out oxygen in particular is very hard to make on Mars. That is, I think beyond our technological horizons — it’s a long time in the future,” he said.
“But warming Mars up, and restoring its thick carbon-dioxide atmosphere, restoring it’s habitable state, is possible,” he stated.
He prefered to call it “ecosynthesis” rather than terraforming. According to him, Mars lived a fast life and died young and it would be a good idea to restore its biosphere.
Lisa Pratt, biogeochemist at Indiana University disagrees with the fact that Mars might be dead. She stated that there is no reason to assume that Mars is sterile or hostile to life.
“I think it’s increasingly evident that there is a large inventory of water on Mars. There may in fact be groundwater relatively close to the surface, meaning within a few hundred meters of the surface,” she explained.
She believes that there is a possibility that the groundwater may be brine, which is a perfectly habitable composition. And that “until we successfully interrogate the Martian subsurface, and adequately address the indigenous Martian organisms”, we should not think about terraforming.
James Kasting, who was co-author on the paper written for journal Nature, on the subject with Chris McKay, thinks that there are two levels of terraforming. One is for plants and the other is for humans. He says he would not like to go through the trouble just to terraform Mars for plants. His interest is human habitation. But in any case, oxygen is a major problem, “it’s not enough just to have photosynthesis, you have to bury the organic carbon you’ve produced.”
He pointed out, “on Earth we bury about one-tenth of 1 percent of primary productivity in the oceans, and that gives oxygen about a four million-year lifetime, meaning you have to do that for four million years.”
He further explained that even if we got really optimistic about the idea and started the oceans on Mars going and reached the same level of productivity as that on Earth and also figured out a way to bury 10 per cent of the organic carbon, “it would still take forty thousand years to build up oxygen. That’s a daunting task which I can hardly envision us doing.”
So in the end he agreed that it would be more doable to terraform it for plants and debate whether that’s worth doing or not.
Greg Bear, author of books such as Moving Mars and Darwin’s Radio,” argued that we must first be sure of our motivations for terraforming Mars.
“Is it because we want to do it for the art of doing it, for the science of doing it, or for the economic necessity of doing it? You know, at this point, it’s kind of tough imagining doing it for any of these reasons, because it would take so darn long,” he stressed.
Also he was of the opinion that if we are doing it for experimental purposes, then the terms of the experiment have to be defined and right now experts do not have that kind of information.
Donna Shirley, the former manager of Nasa’s Mars Exploration Programme at the Jet Propulsion Laboratory, moderated the debate and asked John Rummel, planetary protection officer for Nasa to outline what kind of information was required. In reply, he said that we needed to be sure about the trajectory of Mars.
“The Earth, a couple of billion years ago was not all that comfortable to humans. In fact, we had bacteria that were not really happy when other organisms showed up and started breaking water (molecules) and making oxygen and releasing it into the atmosphere,” he commented.
And these organisms over time modified our planet and its atmosphere. The question is that we need to know, according to him, if we do adopt a trajectory, are there Martian organisms present? In the case of our making Mars more Earth-like, are there organisms present which will resist. For instance, turn the surface into poisonous substances?
Adding a point about Martian life Chris McKay said: “I think that we should make a biosphere on Mars, as I said earlier. I think the ingredients of the biosphere — the genome of that biosphere — if at all possible, should be Martian. That would be a most interesting situation.”
He also pointed out that we already have the information that Mars once had life from the fact that it once had water. An objective assessment of the situation leads us to believe that life might have survived intact even today, maybe dead or frozen in the form of relics.
We could “reconstruct it if we had to, or find it living in some subsurface refuge and let it once again control the biogeochemical cycles of that planet the way that life on Earth controls the biogeochemical cycles of our planet. In other words, give Mars back its heartbeat.”
He thinks that life from Earth should only be sent to Mars as a last resort. That if Mars does not have its own genome than maybe we can share ours with it. But he personally feels that “a Mars full of Martians is much more interesting than Mars full of Earthlings.”
John Rummel, the planetary protection officer at Nasa, feels that a hundred years from now, if scientists on Earth really decided to terraform Mars, they would be able to do it.
“We already have some ideas and we’re getting smarter all the time about how planetary climate works from a technical point of view,” he further added.
But he also presented some profound insight into the subject by pointing out to the interesting fact that mankind must first have the collective decision making abilities that are required to transform any other planet.
“I think if we get to the point where we demonstrate that we have the wisdom to take care of Earth’s climate, and not haphazardly, but in a collective way, where we decide that we’re going to make these decisions and we’re able to control Earth’s climate, then maybe we will have the wisdom to terraform Mars,” he wisely stated.
To the question of finding life on the Red Planet, he advised to wait and watch what was actually going on there in terms of environmental changes.
“I think that if we watch Mars for just a little bit while longer, even if there’s nothing alive there, there are things going on. And those things may or may not lead you to a deduction that life is there.” He stated this in regard to the fact that methane had been detected in the Martian atmosphere. But as he amusingly pointed out, “we haven’t seen the cows yet. I doubt that we’ll find them.”
He also added that it is important to find out about Mars life, if any before we go mixing it up with microbes from Earth. That would modify the environment is a negative way and in one that we might not be able to control.
Conclusion
So, the question still remains, should we or should we not give Mars another chance at life as we know it? Should we leave things be and not play havoc with nature? We have played havoc with our own home planet and are exhausting its resources with great selfish abandon. Or maybe it might be a great service to science if we gave Mars back its “heartbeat.” Let it make its own life, even if it is hostile to life on Earth?
The debate goes on as scientists try to decide and look at the prospects and risks. Greg Bear has also pondered the evolution of humans into Martians. In his book, human beings were genetically modified to survive the Martian atmosphere. He is of the opinion that it is cheaper to fix human beings up rather than fix Mars up. Whatever the future holds, mankind has now embarked on a long relationship with the Red Planet.
The writer
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