Perseverance’s discoveries have reignited the debate on Mars as a possible cradle of past life, but the prospect of human settlement remains a long-term technological and scientific challenge by Andrea Monti – Initially published in Italian by MIT Technology Review Italia
The recent discoveries of the Perseverance rover, which has identified chemical traces that could be interpreted as possible signs of past life on Mars, have reignited interest in exploring the Red Planet. The hypothesis that conditions favourable to life once existed there confirms Mars’ scientific importance. However, alongside the study of the past, the possibility that humans could inhabit the Red Planet today requires the solution of complex problems, one of the most important of which concerns the role of water.
To explore these issues in greater depth, MIT Technology Review Italia met with Goro Komatsu, associate professor in the Department of Engineering and Geology and senior scientist at the International Research School of Planetary Sciences, at the “G. d’Annunzio” University of Chieti-Pescara.
Q: Could you tell us about your research?
One of my main fields of research is Mars geoscience. Essentially, I study the history of the planet and how its environment has changed over time, from the very beginning up to the present day. I am also interested in the current state of Mars: its atmosphere, water inventory and surface landforms.
This research has implications for future human missions, because if humans are to visit or eventually settle on Mars, we must understand these fundamental conditions. One central issue, for example, is where water can be found today.
At present, Mars’ surface is extremely dry and there is no stable liquid water. We know that ice exists in the polar regions, where it is exposed, but at lower latitudes water is thought to exist as buried ice beneath the surface, not visible at the surface.
Q: Why is water such a key resource for human exploration?
Because transporting water from Earth would be extremely difficult. It is heavy and voluminous. If humans eventually establish a base on Mars, it would be far more practical to utilise local water resources. That is why I am especially interested in identifying present-day reservoirs of buried ice.
We believe this ice is a remnant of the much larger volumes of water that existed in the past, when Mars was significantly wetter than it is today. Now, liquid water is absent, and exposed ice is found almost exclusively near the poles. But ground ice may exist in the subsurface at mid-latitudes. My research focuses on how to detect it and where to find it.
Q: How does this connect with the concept of terraforming Mars?
Terraforming is often described in science fiction as the process of making Mars Earth-like. In practice, it would be a vast technological undertaking. Even if we could release subsurface ice to create liquid water, Mars’ atmosphere would remain a fundamental obstacle.
The atmosphere is thin, cold, and composed mostly of carbon dioxide. With Mars’s current atmosphere, any liquid water would boil or freeze quickly or even escape into space over time. Engineers and science fiction writers talk about terraforming, but in reality, what is technologically conceivable in the near future is not full-scale terraforming but building enclosed habitats—domes or bases where ecosystems can be created artificially.
Q: Where would such bases ideally be located?
There is a dilemma. The polar regions have water ice, but they are extremely cold, with limited sunlight. The equatorial and mid-latitude regions are warmer and receive more sunlight, but exposed water is scarce there.
That is why many researchers are looking for ground ice at mid-latitudes. Geomorphological features suggest it exists in the Martian subsurface, and ground-penetrating radar data have supported this. If confirmed, drilling into shallow subsurface ice deposits at mid-latitudes could provide water for long-term human use.
This is similar to permafrost on Earth, found in places like Siberia or Alaska. On Earth, permafrost becomes discontinuous as you move south. We believe the same pattern exists on Mars: continuous permafrost at high latitudes, fragmented deposits further south, and likely localized or none at the equator.
Q: Water seems to be the central driver of competition. Will this shape geopolitical dynamics on Mars?
It may. For initial missions, water may not be essentially problematic, since everything could be brought from Earth. But for long-term settlement, local resources will be critical. That is why many space agencies prioritise identifying water-rich sites.
This is not unique to Mars. On the Moon, interest in polar regions is also tied to evidence of water in permanently shadowed craters.
Whether Mars will become a field of competition depends partly on international law. The situation may resemble Antarctica, where territorial claims are prohibited by treaty, yet nations still stake symbolic claims. If new treaties are not agreed upon, competition for resource-rich sites on Mars could intensify.
Q: Let’s turn to the atmosphere. Does Mars’ low gravity make a breathable atmosphere impossible?
Not impossible, but very difficult. Mars’ gravity is weaker than Earth’s, but atmospheric loss occurs over long timescales. If you introduced enough gases, the atmosphere would persist for millions of years. But creating a breathable atmosphere is a huge challenge.
Earth’s air is a balanced mixture of oxygen, nitrogen, and other gases. Pure oxygen is dangerous; it ignites materials easily. Producing sufficient oxygen from Martian water ice might be possible, but where would nitrogen come from? Without it, the environment would remain unstable.
Moreover, Mars is farther from the Sun than Earth, so greenhouse gases would be needed to raise the temperature. CO₂ and water vapour are greenhouse gases, but the quantities available are uncertain. Even if we reproduced Earth’s atmosphere, Mars might still remain too cold.
Q: So terraforming remains science fiction?
Yes, at least for the foreseeable future. Creating an Earth-like Mars would require technological capabilities and resources far beyond what we currently possess. For the long term, it may remain more practical to build contained settlements rather than attempt to transform the entire planet.
Q: Outside of science, what is driving public fascination with Mars?
Part of it is cultural. Science fiction has shaped people’s imagination of Mars for more than a century. The discovery of thousands of exoplanets has also reinforced the idea that other Earth-like worlds exist, fueling the desire to expand beyond our planet.
Some people are motivated by adventure, others by national pride. Just as the Moon landings were propelled by Cold War competition, future Mars missions may be driven by political motivations as much as by science.
Q: Looking ahead, do you think space colonisation is realistic, or just hype?
Scientifically, there is great value in exploring Mars. But economically, Mars colonisation offers few immediate benefits. Unlike the colonisation of Earth’s continents centuries ago, there are no gold deposits or fertile lands. Without strong political or symbolic incentives, large-scale settlement is unlikely in the near term.
Yet human nature is not purely rational. People take risks and pursue goals beyond immediate logic. Some would volunteer for a one-way trip to Mars, just for the sake of exploration.
Q: Finally, what about humanity’s long-term future in space?
That is what fascinates me most. Over thousands or millions of years, if humans live on Mars or elsewhere, will we remain the same? Or will we evolve physically and culturally in new ways?
Some suggest we may adapt biologically, or even use biotechnology or bioengineering to modify our bodies for survival in different environments. Mars may become a testing ground for such transformations. Others imagine that humanity will retreat into virtual realities instead, living in entirely artificial environments.
In any case, Mars is the most accessible terrestrial planet beyond Earth. Venus is far too hostile, but Mars, while harsh, is at least possible. That is why it has attracted human interest for so long.
Whether through enclosed habitats, bioengineering, or long-term cultural change, Mars represents both a scientific challenge and a mirror for humanity’s future.