The question of whether there is life on Mars has been replaced in recent years with the question of whether there was life on Mars in the past. Until a decade ago, no evidence was found for the existence of organic substances, which provide the basis for life as we know it, but in the last decade there has been a change.
In 2014, for the first time, a robotic mission to Mars identified organic molecules on the planet that could have supported the existence of carbon-based life, like our own. Evidence of a variety of such molecules has since been found in various places on Mars. It is not yet an unequivocal proof, but “Mars is signaling us to keep looking”, said Thomas Zorbuchen, one of the mission managers at NASA.
Indeed, the search has stepped up, and today it focuses on life that looks more or less like the life we know, mainly because the conditions on Mars seem relatively similar to those on Earth. Or rather, they were similar once. Today, the Martian environment seems unsuitable for carbon-based life. The place is dry, the temperatures are extreme and the radiation can break down almost any complex molecule on the surface. But there is evidence that this was not always the case. The planet used to have a real lake, living water, and it had all the materials necessary for organic life.
Prof. Pascal Ehrenfreund, an astrobiologist, is one of the influential people today in space exploration in general and the search for life on Mars in particular. In 2015, she made history when she became the first woman to serve as CEO of one of the eight major space agencies (DLR). Today, she heads the first international university for space research and heads the IAF, the International Astronautical Organization, which serves as a ground for coordination between academia, industry and space agencies. In an interview with Globes, she talks about the different directions in which space research is going, between the search for life on Mars and the return of manned missions to the moon.
The ingredients of the ancient soup
“If in the past we were excited to find carbon on Mars, today we even find amino acids, the substances that are at the base of proteins, on meteorites that seem to originate from Mars,” Ehrenfreund says. “In other words, we see in space most of the materials that make us up. We haven’t seen life yet, not even simple life, but we have seen the molecules that are the basis of life.”
Ehrenfreund is involved in projects to search for bacteria on Mars and more distant stars, and she is very optimistic. According to her, “It is entirely probable that we will recognize such simple creatures in the next 20 years.” The search was made with several tools that are on Mars at this very moment, and in the next decade new findings are expected to come from them at a dizzying pace.
Only in the last year, organic molecules were found by the new robotic vehicle Presbyrans in areas not covered by the previous robotic vehicle Curiosity. Presbyrans can also drill deeper, to places where perhaps more complex molecules have survived longer, protected from the radiation.
To know what to look for as a sign of life on other stars, astronauts first looked for the first signs of life on Earth. In her lectures, Ehrenfreund says that when the Earth was just formed, it was an unsympathetic place. “Actually, it looks quite similar to hell. Geological activity and radiation made it a hostile place where life could not be created, but 3.5 million years ago, there are already signs of life. We believe that the ‘primordial soup’ was formed in the depths of the sea or in volcanic areas. Then , a meteor may have brought materials to Earth that it could have used to create this change.”
This early evidence of early life is also what is now being sought on Mars. “Very ancient stones teach us about the existence of equally ancient bacteria, which lived without oxygen, and perhaps even ate stones,” says Ehrenfreund. One of the evidences of these ancient bacteria are stromatolites, a kind of “bacteria fossils”. On Earth, they are found in the depths of the sea, in places where streams of hot water are released from the bottom of the sea. Over time, the bacteria die and a sediment accumulates between the layers of the dead material, which then decomposes, but leaves stone streaks with a characteristic structure.
While organic molecules are not a clear and unequivocal sign of life (ultraviolet light from the sun can affect carbon dioxide so that it becomes a more complex molecule, even without life), there is agreement regarding stromatolites. Some leading experts in astrobiology have said in the past that such structures, if found on Mars, would be considered pretty clear evidence that there was once carbonaceous life on the planet, especially if they were found in several places.
When there is life, it is everywhere
In the last decade, several other findings have been received that ignite the imagination of researchers in this field. One of them is that Mars produces methane. On Earth, methane production is the result of the activity of living things. The robotic vehicle Curiosity modeled methane on Mars, and not only that: it detected seasonal fluctuations in its levels and sudden increases of unknown origin. I mean, Mars seems to be producing methane right now. This too can have geological explanations that are not related to life. The source of methane on Mars is still a mystery.
Another find is a substance called jarosite, a yellowish mineral that as far as we know only forms in wet environments. This mineral appears to be relatively young, meaning it may be from the period after the water in the star dried up. Was there moisture left below the surface that could sustain organic life or a certain type of bacteria, even years after Mars became hellish? Aronfreud does not rule out this possibility.
“The interesting thing about life as we know it,” she says, “is that once there was life on Earth, it was everywhere. Even in Antarctica, deep in the sea at high pressures, or in very acidic environments, or deep in the earth. Even in containers where radioactive waste is thrown We see bacteria that feed on these substances. All the time we find more types of bacteria, some of them very different from the ones we already know, and it’s quite clear that the bacteria control the soil and not us.” If life did form on Mars, it is possible that it was able to survive the changes that occurred there.
The Perseverance mission has already confirmed Curiosity’s findings of the existence of organic molecules, but the instruments on the robotic vehicle are not sophisticated enough to study them. These samples are supposed to land here in 2023, so there is something to look forward to.
Is there a chance that Mars managed to hide from us until today life more complex than bacteria?
“We are certainly not talking about aliens. We know Mars well enough to know that there is no civilization there. We are looking for large, complex molecules, not only to know what is currently on Mars or what was, but also what could be, that is, if we can To build life on Mars.”
The bacteria are getting stronger
What are the chances that we will live on Mars in our lifetime? On the face of it, it doesn’t sound like fun. “The atmosphere is very toxic and temperatures are very fluctuating, the radiation is strong and there is no running water. Nevertheless, we have road maps going forward and we think we can bring humans to Mars in a few decades,” says Ehrenfreund.
Living on Mars is not on the agenda in the distant future. A short visit will probably be possible in a few decades, but it’s no picnic either. “In the coming decades, the most important thing is to study how staying in space affects the health of the astronauts. The road to Mars is long (about seven months under current conditions) and we also have to come back. We anticipate a variety of health problems, muscle problems, bone problems, problems with the cardiovascular system and the immune system. There is also the psychological issue. The distance from home, the isolation, the social relations in the group.”
Ehrenfreund herself investigated “something that stresses us out a bit”, as she says. “The human immune system probably weakens in space, and on the other hand the bacteria get stronger, we see that bacteria are very resistant to different conditions. They survive the radiation better than us and also the microgravity. So on the one hand we fear them, and on the other hand we want to understand how they do That. As they are today, they can probably survive on Mars and we can’t. If we bring them to Mars, we could create a big pollution there.
“Nor does anyone know if their response to antibiotics in space is the same as on Earth – although that is our hope. For these reasons, currently a manned expedition to Mars is not on the agenda.”
Elon Musk, one of the leaders of the private space industry, has previously said that he believes he will die on Mars. That is, he plans to go on a trip there and takes into account that there might not be a return trip. Is this something you are considering?
“No way. I don’t agree with it on an ethical level and the space agencies are very clear in their approach to the matter. We are not ready to plan a mission where it is known that people will not return. I am not even ready to imagine that.”
The moon is part of us
Although Ehrenfreund rejects Musk’s statement, she very much welcomes the entry of commercial companies into the field of space. “They speed up the development processes many times more than in a world where only government agencies and government budgets are involved. But we want to see the process speed up much more,” she says.
The commercial companies have a role not only in building spaceships and satellites, but also in developing the materials from which the spaceship is made and the astronauts’ equipment. We received an example of this in NASA’s Artemis 1 mission to the moon, the launch of which was postponed for a month, after several failed launch attempts. One of the experiments that will be included in this mission is the Zohar experiment – a dummy with a protective vest from the Israeli company Starmed. The purpose of the experiment is to show that the vest absorbs less radiation than “Helga”, the puppet of the competing space company. If Zohar wins, the Israeli vest will become the official vest of Artemis, which will eventually land astronauts on the moon again, after many decades of not visiting there.
“We are very interested in the moon because it is a part of the earth, in fact. It was torn from it apparently due to the collision of another object with the earth at the beginning of the earth’s life. The moon combines materials from the earth together with the materials from the other object, and has accompanied us from the beginning.
“Our Earth has been changed by water, wind, and we don’t have the information from its early days. If we want to get to ancient rocks, we have to dig really, really deep, or go to the moon and understand what happened in the early days of our Earth. That’s where life actually happened. The more we return to the moon, the more we will learn about it, but also about ourselves.”
Prof. Pascal Ehrenfreund / Photo: Reuters, Nick Zonna/IPA/Sipa USA
According to Ehrenfreund, there is another reason why it is worth going back to the moon. “It’s easy to research technology there that will be used by us in the future to reach and explore other stars. For example, robots that engage in mining, and the way you can build in the gravitational conditions of the moon. We plan to test the use of water there, and possibly agriculture as well. The moon can certainly be a stepping stone to Mars. It is of course More accessible. Even Israel already has the ability to reach the moon.”
Will we be able to live there in the near future?
“In the near term, living in a space station around the moon is easier. The Artemis mission is already building the space station where astronauts will live and jump to the moon from time to time. I don’t see the establishment of a new settlement on the moon in the foreseeable future.”
Prof. Pascal Ehrenfreund
personal: 61 years old, born in Austria, holds a master’s degree in molecular biology and a doctorate in astrophysics and astrochemistry from the University of Vienna
professional: President of the International Space University. She previously served as a professor at the universities of Leiden, Amsterdam and Redbout Nijmegen in the Netherlands. In addition to her academic positions, she led the Austrian Science Foundation, headed the German Space Research Center, one of the eight major space agencies, and was a visiting researcher at the Jet Propulsion Laboratories and NASA’s Astrobiology Institute
Something else: Asteroid 9826 was named after her in 2000, as a token of appreciation for her contribution to the study of astrobiology
The Space University that connects research and industry
The International Space University was established in 1987 by four young people who were involved in the field of space from different directions. Today it offers master’s degree programs in the field of space, and special study programs, some in collaboration with other academic institutes, space agencies and industry. Apart from space and related subjects required for its study, the university does not offer courses in any other subject (except sports). This coming November, the Space University will hold, for the second time, a joint course with the Ramon Foundation and the Ernst & Young Company for managers in the space industry.
Most of the university’s faculty consists of space agency personnel and academics from other universities. Ehrenfreund was preceded by astronaut Buzz Aldrin, the second man to walk on the moon.
The founders of the university are Peter Diamandis, a doctor with a master’s degree in space engineering from MIT and the founder of the International Association of Space Students; Todd Hawley, a graduate of the Space Policy Institute at George Washington University in the US; Robert Richards, an engineer and physicist; and Christopher Mao, a venture capitalist. The four held a competition between different cities to choose the one that would host the central campus and finally they chose Strasbourg In 2004, the project was recognized as a university. Since its establishment, the university has also been active in space policy, and is recognized as a regular participant in the UN Committee on the Peaceful Uses of Space.
3 signs that may indicate life on Mars
1. Stromatolites: A kind of fossils of bacteria, which on earth are found in the depths of the sea. Among the researchers there is an agreement that if they are found on Mars, it will be evidence that there was life there
2. Methane: In the last decade, evidence has been received that Mars produces methane, a gas on Earth that is the result of the activity of living beings. The source of the methane there is still a mystery
3. Gerosite: A yellowish mineral, which as far as is known forms in wet environments. The mineral found on Mars appears to be relatively young, meaning that water may have survived deep in the Martian soil even after it dried up