The research team is proposing a major philosophical change in our thinking about the spread of terrestrial microbes in space, especially on Mars. Believing that interplanetary pollution is 'inevitable', the team argues that future Martian colonists should use microorganisms to transform the Red Planet – a proposal considered by some experts to be grossly premature.
In an article published last month in FEMS Microbiology Ecology, microbiologist Jose Lopez, a professor at Nova Southeastern University in Florida, along with colleagues W. Raquel Peixoto and Alexandre Rosado from the Federal University of Rio de Janeiro, proposed a "serious revision" of current underlying philosophies space exploration and planet protection policies related to the spread of microorganisms in space.
Instead of worrying about contamination of foreign celestial bodies – something that NASA and other space agencies are trying to avoid – Lopez and his co-authors say that we should deliberately send our germs to space and that the spread of our microbes should be part of a larger colonization strategy to tame climate on Mars. The key argument proposed by scientists is that pollution prevention is "almost impossible" as the authors express in the study.
"The introduction of microorganisms should not be considered accidental but inevitable."
Such a policy change would be a clear contrast to conventional thinking on this issue. Some of the experts we spoke to say that the protocols that are currently in force to prevent pollution of another planet are probably working to the best of our knowledge and we should not give up so easily. What's more, experts have said that there is still a lot of science to be learned on Mars and elsewhere before we consider this unrecoverable possibility.
Currently, a larger scientific community agrees on the need to prevent microbial contamination of planetary bodies such as Mars. NASA, ESA and other space agencies carefully and expensive sterilize their instruments before launching them towards neighboring celestial targets.
The philosophy of planetary protection, or PP, dates back to the late 1950s and the uprising Space Research Committee (COSPAR), appointed by the International Council of Scientific Unions. COSPAR, among other things, develops recommendations and protocols designed to protect space against our microbes. In this regard, the UN Space Treaty, signed by over 100 nations, clearly states:
Treaty States Parties will conduct space research, including the moon and other celestial bodies, and research them to avoid their harmful pollution as well as adverse changes in the Earth's environment resulting from the introduction of extraterrestrial matter and, if necessary, take appropriate measures For this purpose. If a State Party to the Treaty has reason to believe that the space activities or experiments planned by itself or its citizens, including the Moon and other celestial bodies, would cause a potentially harmful interference with the activities of other States Parties in peaceful exploration and use of space, in including the moon and other celestial bodies, undertake appropriate international consultations before undertaking such activities or experiments.
The basic justification for this thinking is that our germs can potentially contaminate scientifically important places in the Solar System, thus spoiling our ability to detect the local life of microbes on Mars and other worlds. For example, finding traces of DNA or RNA on Mars would not automatically mean that they came from Earth, because these molecules can be a fundamental and ubiquitous element of evolution in the universe. Perhaps even more problematically, he is afraid that the invasive earthly life may be extinguished by an alien ecosystem before we have the chance to explore it.
On the other hand, Lopez and his colleagues believe that it will be impossible to prevent germs from getting to the places we study, so we might as well have a rational discussion about the best use of microorganisms in our favor. In particular, the authors refer to the perspective of terraforming – the hypothetical practice of planetary geoengineering to make it more similar to Earth.
Looking at the Earth's ancient history as a precedent, the authors recognize the extremely important role that microorganisms play in encouraging human habitation, including oxygen production, regulation of gases such as carbon dioxide, methane and nitrogen, and decomposition of organic and inorganic materials.
"Life as we know it cannot exist without beneficial microorganisms," said Lopez in a NSU press release. "They are here on our planet and help define symbiotic associations – the joint life of many organisms to create a larger whole. To survive on sterile (and as far as ever, all travels) sterile planets, we will need to bring beneficial microbes with us [to Mars]. Preparation, research will take some time, and we are not in favor of the rush to vaccinate, but only after rigorous, systematic research on earth. "
The key to their argument is acknowledging our transition from explorers to colonists. The authors say that life may have existed or existed elsewhere in the solar system. "The lack of any discoveries or evidence of life from over 70 space missions and probes that have left Earth's orbit indicate only one unique presence of life in our direct solar system," they write.
Lopez and his colleagues say that if we take colonization of Mars seriously, we will have to consider the role our microbes play. It is said, however, that the spread of germs on Mars should not occur without discrimination and without careful prediction.
"Instead, we foresee a purposeful and measured research program on colonization of microorganisms that implements the limitations of current technologies. That is why we are in favor of a conservative timetable for introducing microorganisms into space, while realizing that human colonization cannot be separated from the introduction of microorganisms. "
To this end, scientists propose a proactive vaccination plan or PIP. Such a plan would be introduced before any long-term mission and would require a review of promising bacterial candidates. Dangerous microbes will be rejected, and only "most productive" microbes will be included in future missions, the authors write:
If humanity is seriously considering the colonization of Mars, another planet or one of the nearby moons in the future, people must identify, understand and send the most competitive and useful pioneers. Selection or development of the most persistent microorganism [species] or communities can be created with the help of considerations, systematic research and current data, instead of accidentally sending bacteria accidentally hitchhiking at space stations.
Extremophils – microbes capable of living in the toughest environments on Earth – would be the first microbes scattered to Mars, probably buried a few feet underground to protect them from frost and surface radiation.
However, as the authors themselves admit, "total control of the full list of microorganisms [species] and their genomes sent into space can never be realistically reached, "and" the recovery of microbes once sent may not be possible. " In other words, we will never have full control or knowledge about this process, nor will we be able to stop it when we start.
The authors did not provide any details about when the first microbes should be planted on Mars, or how long it would take for microorganisms to achieve the desired effects – assuming it would work. An open question, for example, can microbes, and even extremophiles, function on the surface of Mars, where extremely low air pressure rises around a miserable 0.7 kPa, which is not too far from the conditions in space. Low gravity on Mars along with intense solar radiation falling on the surface further complicate the image.
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But even if it works, the time frames involved should discourage even the most optimistic would-be Martian colonists. On Earth, these processes required hundreds of thousands, perhaps millions of years of microbiological churning of the patient (e.g., oxygen production through photosynthesis by cyanobacteria).
Bruce Jakosky, a professor of geology at the University of Colorado and an expert on the prospects of terraforming Mars, said the authors are proposing some "very dramatic changes" to the global planet protection protocol, as he wrote in an email to Gizmodo.
"These [recommendations] they seem to conflict with the decades of approach we have taken to PP, "Jakosky said. "I welcome the possibility of further discussion on how PPs should be implemented and whether changes should be made to it, but I am worried about suggestions that recommend such changes on a wholesale scale without carefully examining their consequences with an impartial view."
Physicist Todd Huffman of the University of Oxford said that the authors made a logic mistake, saying that it is impossible to completely sterilize a space ship on Earth, so we should not even try. Huffman believes that we should definitely try and that there is a very good chance that we will succeed thanks to our planet protection plans, be it through Earth's protocols, the devastating effects of space exposure, or the harsh conditions already on Mars.
"Since 1976, quite a few probes have landed on the surface of Mars. They have all been subjected to extreme COSPAR sterilization protocols so far, "he wrote in an email to Hizmana to Gizmodo. "And to this day none of them detected Martian or terrestrial microbes or their evidence. Which means that COSPAR protocols actually work. Therefore, their arguments are not only based on their own merits, but their claim that you cannot keep pollution away from a planet like Mars has proved to be unfounded so far, "he said. To which he added: "I believe that if it has not broken, do not fix it. COSPAR protocols appear to keep earthly worms away from Mars when we study this planet for all native organisms. We shouldn't mess with them unless we want to sharpen them. "
Huffman disagrees that we might eventually want to introduce microbes to Mars as described by the authors, but "it would be a huge scientific mistake to relax the COSPAR protocols in every world that we still have to define as dead," requiring us to "stay away from Mars, Europe, Enceladus and maybe even Titan, "he said. "At least for now."
"We must follow the planetary counterpart of the Hippocratic Oath:" Above all, do no harm. "
Steve Clifford, a senior scientist at the Planetary Science Institute, said he had "serious concerns" about the new article. Ultimately, he believes that the potential consequences of making a mistake by relaxing the planet's standards of protection "far outweigh any short-term gains." He said we could eventually pollute Mars, but by then "we must obey the planetary counterpart of the Hippocrates Oath:" Above all, do no harm. "
"I think the potential pollution of a foreign biosphere is a serious ethical problem – because it's a legacy that we carry with us forever," said Clifford in an email to Gizmodo. Like Huffman, he is concerned that earth germs can complicate our ability to learn on Mars, and said there is no reason to believe that current planet protection systems are not working.
"If life evolved on Mars or below the oceans of the ice moons of outer planets, it probably survived on these bodies for billions of years," said Clifford. "Detecting life on any of these bodies would be of great importance in our understanding of the universality of life in the universe."
Regarding claims that the implementation of planetary protection protocols is too expensive, Clifford said the associated additional costs, which are usually around Worth 20 percent of mission costs.
"When exploring potentially habitable environments in our solar system, we must respond – as definitively as possible – to the presence of any native life before we ever send people there," said Clifford. "And if these environments prove dead, the need to comply with current planetary protection standards will disappear. However, if we discover life, I think we need to have a serious discussion that balances our desire to colonize and utilize the resources of the Solar System, contrary to the ethical concern to cause the potential extinction of the first examples of alien life we have found. "
At the same time, he does not believe that there is a sort of obvious destiny to colonize the solar system before we have the opportunity to conduct a thorough search for the lives of strangers, "whether this search will take 50 years or a few centuries," he said. Until then, "there are many dead places in the solar system – such as the moon and asteroids – from which people can explore, colonize and extract resources," said Clifford.
Lopez and his colleagues apparently hit a sore spot. None of the experts we spoke to had major reservations about the use of microorganisms as part of the colonization and terraformation process at some point. On the contrary, they were irritated by the claim that we are close to moving from the exploration to colonization stage and that we should begin to properly mobilize our resources – and our microbiological resources.
As we approach the era in which we are able to send people to the Red Planet, this debate will no doubt be hot.