They propose a revolutionary plan to rehabilitate Mars.

This is the dream that many scientists have been dreaming of for almost a century, the same dream that Carl Sagan already proposed in 1971 and to which all sorts of ideas have been devoted, from turning one of its moons into a mini-sun to flooding its fragile atmosphere with billions of tons of greenhouse gases, or planting the entire planet with lichens and bacteria capable of producing enough oxygen. Plans that are mostly unachievable, or very expensive, and that, in the best case, could take centuries to implement.

But all that could change thanks to a groundbreaking study just published inScience advances‘By a team of researchers from the University of Central Florida, Northwestern University and the University of Chicago. A study that allows us, for the first time, to address the process of terraforming Mars with a plan that is technically feasible, much more economical than any previous plans, and can be implemented in record time.

metal particles

The new method, which relies on manufacturing and launching tiny metal particles in the form of “rods” into the atmosphere, would allow the average temperature of Mars, which is currently around -65 degrees, to rise by 10 degrees in just a few months and become habitable, initially only for bacteria and cultures, in just a few decades. According to the researchers, the proposed method is 5,000 times more efficient than any previous methods.

In fact, terraforming plans in the 1980s and 1990s proposed bringing millions and millions of tons of greenhouse gases to Mars from Earth to achieve what we are doing here, involuntarily, on our own planet: warming it up. The bad news is that millions of tons of these gases would be needed, and transporting them from here to Mars would be very expensive.

To avoid this insurmountable obstacle, it was also proposed to build hundreds of “pollution factories” on Mars with the sole purpose of releasing gases into the Martian atmosphere until it became dense enough to retain heat. But the materials needed to build these factories were again too numerous to be carried on spaceships. The idea was improved somewhat by the proposal to send “self-replicating robots” to the Red Planet, which would obtain the necessary materials from Mars itself to multiply their numbers and build the necessary factories. But the technical difficulties proved practically insurmountable, and the project also proposed a timetable for achieving the goal lasting several centuries.

Cheaper, faster and… possible.

But for electrical engineer Samaneh Ansari, of Northwestern University and lead author of the new paper, these changes could be achieved much faster and thousands of times cheaper by filling the atmosphere with millions of microscopic metal rods, which would be able to create and sustain the greenhouse effect.

The main advantage of the new solution is that it does not rely on transporting gases or heavy building materials from Earth to Mars, but can be achieved by processing materials that are already abundant on the Red Planet.

We actually know that Martian dust is rich in iron and aluminum. While these dust particles alone are not suitable for warming the planet, they could be used to engineer other particles with different shapes or compositions that trap heat more efficiently.

“It would take millions of tons[of these particles]to warm the planet, but that’s 5,000 times less than what we would need,” says Edwin Kite, of the University of Chicago and a co-author of the paper. “Previous proposals for global warming on Mars have been met with global warming, which greatly increases the feasibility of the project.” This suggests that the barrier to Mars warming enough to allow liquid water to exist is not as high as previously thought.”

Red Planet Warming Up

So, Al-Ansari and his colleagues designed metal particles in the form of very short rods, similar to those made of glitter, specifically designed to trap heat escaping from Mars while simultaneously scattering sunlight toward the planet’s surface, doubling the natural greenhouse effect.

“It’s amazing that light can interact with objects below its wavelength,” Ansari explains. “But what’s even more important is that these engineered nanoparticles can cause optical effects far beyond what is typically expected from such small particles.”

Calculations, in fact, suggest that if particles were ejected into the Martian atmosphere at a constant rate of 30 liters per second, the planet would warm by more than 10 degrees in just a few months. Moreover, the warming would be “reversible,” meaning it would stop within a few years once the particles were no longer emitted.

Of course, the researchers say there’s still a lot of work to be done. For example, it’s not yet known how quickly dust injected into the atmosphere is lost to space (all planetary atmospheres leak). It’s also possible that as the planet warms, the water that continues to “leak” from the planet today will begin to condense more and more around the particles themselves and end up falling back on them as rain.

“Climate feedbacks are really hard to model accurately,” Kite warns. “To get something like that, we first need to get more data from both Mars and Earth, and we’ll have to go slowly and backwards to make sure the effects work as intended.”

Overall, the proposed new method is revolutionary and represents a significant advance in terraforming research. The researchers emphasize that, for now, their work is focused on warming Mars enough for microbial life and perhaps growing food, not on creating an atmosphere that would allow humans to breathe. “This research opens up new avenues of exploration and may bring us one step closer to the long-held dream of a sustainable human presence on Mars,” Kite concludes.