Mars is a frozen shadow of its former self. Its riverbeds are dry, its air is thin and chock-full of carbon dioxide, and its soil is soaked with salts hostile to life. Yet beneath the red dust lies planet-sized potential — a planet that once had lakes and skies and, perhaps, the right conditions for life to begin.

Now, a team of researchers wants to nudge Mars back toward that lost possibility, not out of nostalgia, but to ask a deeper question: can a dead world be brought back to life?

These scientists are not proposing a colony or a biodome. They are talking about something far more audacious — reshaping a planet’s climate, engineering its chemistry, and seeding it with Earth life.

They want to terraform Mars.

In a new paper, a group of planetary scientists, biologists, and engineers make the case for treating Mars as the ultimate ecological experiment. The study, led by Erika Alden DeBenedictis of Pioneer Research Labs, outlines a phased plan for making Mars habitable over centuries.

For decades, the idea of terraforming Mars belonged to the realm of science fiction. Now, scientists are saying it’s time to treat it as science.

“Thirty years ago, terraforming Mars wasn’t just hard — it was impossible,” DeBenedictis told Space.com. “But new technology like [SpaceX’s] Starship and synthetic biology have now made it a real possibility.”

A New Case for Terraforming

The paper proposes that recent advances in climate engineering, synthetic biology, and spaceflight justify a fresh research agenda.

Mars is cold. Its average temperature hovers around minus 70°C, and its paper-thin atmosphere — just 0.6% the pressure of Earth’s — can’t support liquid water for long. The first step toward terraforming is to heat things up.

The study outlines a phased approach. The first phase is abiotic: warm the Martian surface using new techniques like solar sails, engineered aerosols, or tiling areas with ultralight silica aerogels. These methods aim to raise surface temperatures by at least 30°C — enough to melt some of the ice locked in Mars’ frozen soil. This would trigger a feedback loop that would see even more greenhouse gases dumped into the atmosphere.

Currently, Mars receives only about 130 watts of solar energy per square meter — far less than Earth. But its thin atmosphere means that even small changes in heat input could dramatically alter its climate.

“Together, advances in Earth’s launch capacity, combined with proposed new warming techniques, could potentially raise Mars’ temperature by 30°C well within the century,” the authors write.

From Biology to Biosphere

In phase two, the focus would shift to life. Genetically engineered extremophile microbes — built to survive Mars’ cold, radiation, and toxic salts — would be introduced to establish the first biological footholds. Some could even use perchlorate salts, common on Mars, as a metabolic energy source.

“We now know that Mars was habitable in the past, from data returned by the Mars rovers,” said co-author Edwin Kite of the University of Chicago. “So, greening Mars could be viewed as the ultimate environmental restoration challenge.”

These organisms would help kick off ecological succession, creating organic matter, releasing oxygen, and slowly changing the chemistry of the surface and atmosphere.

Phase three would be the longest and most ambitious: building a stable biosphere that includes oxygen-rich air, potentially breathable by humans. The goal is a 0.1 bar oxygen atmosphere — enough to sustain human life without pressure suits.

“Life is precious — we know of nowhere else in the universe where it exists,” said Harvard planetary scientist Robin Wordsworth. “We have a duty to conserve it on Earth, but also to consider how we could begin to propagate it to other worlds.”

Risks, Rewards, and Ethics

Terraforming Mars isn’t just about what’s possible. It’s also about what’s right.

“If we decide to terraform Mars, then we will really change it in ways that may or may not be reversible,” cautioned co-author Nina Lanza, a planetary scientist at Los Alamos National Laboratory. “Mars is its own planet and has its own history.”

“If we modify the environment on Mars, we’re going to change the chemistry of the surface and of the subsurface, eventually,” said Lanza. “Such actions might erase any traces of life on Mars.”

That’s why the authors call for a significant ramp-up in Mars exploration. And this includes NASA’s Mars Sample Return mission and future subsurface investigations. Before introducing Earth life, they argue, we must do everything possible to detect indigenous Martian life, if it exists.

Still, the study’s authors suggest that Mars might be the ideal place to test new ideas about planetary engineering. Unlike Earth, Mars has no entrenched industries or political constraints. It’s already dead and barren. Plus, who knows what we can learn from transforming Mars. Green technologies developed for Mars — such as desiccation-resistant crops, or closed-loop biospheres — might one day help us adapt to climate change at home.

“Developing green technologies for space is a powerful strategy for maturing it for use on Earth,” said DeBenedictis. “Mars is a unique target market because it has no oil, no existing infrastructure and no status quo.”

From Theory to Action

While building a green Mars may take centuries or longer, the authors argue that we must begin now. That doesn’t mean launching grand geoengineering projects today. It means preparing.

“Upcoming Mars surface missions in 2028 or 2031 should include small-scale experiments to de-risk terraforming strategies, such as warming localized regions,” said DeBenedictis.

The technical path forward includes modeling climate feedbacks, designing new life-supporting materials, and engineering hardy microorganisms in Mars-like chambers on Earth. The team also calls for careful laboratory studies of aerosols and solar reflectors before any future field tests.

Any deployed technology, they note, must be reversible, controllable, and biologically safe.

“We should really keep doing science — it’s transformational,” said Lanza.

Ultimately, the paper suggests that the future of Mars may depend not just on rockets and microbes, but on our willingness to learn. Terraforming, in this vision, isn’t a reckless escape from Earth’s problems. It’s an invitation to understand our own biosphere better — by trying to build one from scratch.

“We don’t even know what’s physically or biologically possible. … If people can learn how to terraform a world such as Mars, this may be the first step to destinations beyond,” the authors write.

The findings appeared in the journal Nature Astronomy.