Scientists Reveal Easy Three-Step Plan to Terraform Mars

Yahoo

18 hours ago

Terraforming, the act of radically transforming a planet's climate and environment to make it suitable for human habitation, currently belongs to the realm of science-fiction. But it's possible, at least in theory, and the idea of terraforming our nearest candidate planet for off-world colonization, Mars, has captivated us for generations.
But how would we even begin to pull off such a monumental feat of engineering? You can basically boil it down to three simple steps, argue the authors of a recent study published in the journal Nature Astronomy, who are encouraged by recent breakthroughs in several fields.
"Thirty years ago, terraforming Mars wasn't just hard — it was impossible," lead author Erika DeBenedictis, CEO of Pioneer Labs, told Space.com. "But new technology like Starship and synthetic biology have now made it a real possibility."
The inclusion of Starship, the Elon-Musk owned SpaceX megarocket, may warrant some pushback, since it's faced several high-profile failures and is likely far from being completed. But the fact that a spacecraft of its scale is even being attempted at all is at least worth something.
Alright, but assuming we can make the trip to the Red Planet, how do we turn it into something approaching a green one?
Recent advances in Mars science suggest that the planet's vast stores of ice harbor enough water to form an ocean around 1,000 feet deep across 3,800,000 million square miles of the planet. And according to the study, these frigid seas-in-waiting could start melting with a temperature increase of at least 30 degrees Celsius. (There also appears to be subterranean oceans hidden beneath the surface.)
So that's the first step. One way this could be achieved is by harnessing solar sails as mirrors to focus more light on the planet. This could be combined with dispersing aerosols in the atmosphere to accelerate the greenhouse effect, while techniques such as coating the Martian surface with particles called silica aerogels could help drive heating locally. Combined, the researchers estimated that the 30 degrees of warming could be achieved within the century.
The next step involves getting a little help from tiny, anaerobic creatures that can survive the harshest environments: extremophiles. To serve as "pioneer species," we would likely have to genetically engineer these organisms so they can withstand Mars' low pressure and its cold temperatures, which swing wildly. As the planet's ancient water is liberated from its icy tombs, the first surfaces bodies of water will be extremely salty brines, which many microbes on Earth are capable of surviving, the authors write. Once these microbial critters take hold, they'd go to work reforming the planet's chemistry and laying the groundwork for a food-producing ecosystem.
The final phase, however, is both the longest and most ambitious: shoring up the Martian atmosphere so that it can support diverse plant life and other organisms. To pull it off, terraformers would need to create at least a 100 millibar oxygen atmosphere, the authors write, or about a tenth of the Earth's average atmosphere at sea level.
We could initially achieve this in large, 100-meter-tall domed habitats, they speculate. Outside of these habitats, the spread of plant life would passively contribute oxygen to the atmosphere — but this process on its own would take a millennium. We could artificially accelerate this, write the authors, by freeing oxygen from the melted water, but more research is needed to determine if the materials necessary to accomplish that are abundant on Mars so that they wouldn't be required to be imported from Earth in prohibitively large quantities.
"We now know that Mars was habitable in the past, from data returned by the Mars rovers, so greening Mars could be viewed as the ultimate environmental restoration challenge," coauthor Edwin Kite, an associate professor at the University of Chicago, told Space.com.
As tempting as it would be for humanity to rise to the challenge, there are serious ethical and scientific questions to be raised about terraforming an entire planet, especially one that may have harbored life in the past, or perhaps still does.
"If we decide to terraform Mars, then we will really change it in ways that may or may not be reversible," coauthor Nina Lanza, a planetary scientist at Los Alamos National Laboratory, told Space.com. "Mars is its own planet and has its own history. When we terraform, then we effectively don't have the opportunity to study that anymore, and we may lose knowledge about how planets form and evolve."
Of course, this remains speculative — it's serious speculation, but speculation all the same. For all the promising advances we've made, we still haven't proven we can send a tiny payload of samples back from Mars, or even demonstrate that our putative best shot of getting there, Starship, is spaceworthy. But, as they say: all in good time.
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