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Is it possible to one day make Mars like Earth? – Tyla, 16, Mississippi
When I was in high school, my biology teacher showed our class the sci-fi movie Star Trek III: The Search for Spock.
The plot drew me in, with its description of the “Genesis Project” – a new technology that transformed a dead alien world into a world teeming with life.
After watching the movie, my teacher asked us to write an essay about such a technology. Was it realistic? Was it ethical? And to channel our inner Spock: Was it logical? This assignment had a great impact on me.
Fast forward to today, and I’m an engineer and professor developing technology to extend human presence beyond Earth.
For example: I am working on advanced propulsion systems to take spacecraft beyond Earth orbit. I am helping to develop lunar construction technologies to support NASA’s goal of a long-term human presence on the Moon. And I was on a team that showed how to 3D print habitats on Mars.
To support people beyond Earth will take a lot of time, energy and imagination. But engineers and scientists are beginning to sidestep the many challenges.
NASA/JPL-Caltech
A partial checklist: Food, water, shelter, air
After the Moon, the next logical place for humans to live beyond Earth is Mars.
But is it possible to terraform Mars—that is, transform it to resemble Earth and support life? Or is it just the thoughts of science fiction?
To live on Mars, humans will need liquid water, food, shelter, and an atmosphere with enough oxygen to breathe and thick enough to retain heat and protect against radiation from the Sun.
But the Martian atmosphere is almost all carbon dioxide, with virtually no oxygen. And it’s very thin – only about 1% as dense as Earth’s.
The less dense an atmosphere, the less heat it can hold. The Earth’s atmosphere is thick enough to hold enough heat to sustain life in what is known as the greenhouse effect.
But on Mars, the atmosphere is so light that nighttime temperatures routinely drop to minus 150 degrees Fahrenheit (-101 degrees Celsius).
So what’s the best way to give Mars an atmosphere?
Although Mars has no active volcano right now – at least as far as we know – scientists can trigger volcanic eruptions through nuclear explosions. Gases trapped deep in a volcano would be released and then moved into the atmosphere. But this scheme is a bit strange, because the explosions would also introduce deadly radioactive material into the air.
A better idea: Redirect water-rich comets and asteroids to crash into Mars. This too would release gases from beneath the planet’s surface into the atmosphere, while also releasing the water found in comets. NASA has already demonstrated that it is possible to redirect asteroids – but relatively large ones, and lots of them, are needed to make a difference.
Making Mars cozy
There are many ways to warm the planet. For example, giant mirrors, built in space and placed in orbit around Mars, can reflect sunlight on the surface and heat it.
A recent study proposed that Mars colonists could spread airgel, an ultralight solid material, on the ground. The airgel would act as an insulator and trap heat. This could be done all over Mars, including the polar ice caps, where the airgel could melt existing ice to make liquid water.
To grow food, you need land. On Earth, soil is made up of five components: minerals, organic matter, living organisms, gases, and water.
But Mars is covered in a blanket of loose dust-like material called regolith. Think of it as Martian sand. Regolith contains few nutrients, not enough for healthy plant growth, and contains some nasty chemicals called perchlorates, used on Earth in fireworks and explosives.
Cleaning the regolith and turning it into something practical would not be easy. What the alien soil needs is a Martian fertilizer, perhaps made by adding extremophiles to it – hardy microbes imported from Earth that can survive even the harshest conditions. Genetically engineered organisms are also a possibility.
Through photosynthesis, these organisms would begin converting carbon dioxide into oxygen. Eventually, as Mars became friendlier to terrestrial organisms, the colonists could introduce more complex plants and even animals.
Providing oxygen, water and food in the right proportions is extremely complicated. On Earth, scientists have tried to simulate this in Biosphere 2, a closed ecosystem containing oceanic, tropical and desert habitats. Although all of Biosphere 2’s environments are controlled, even there scientists struggle to strike the right balance. Mother Nature really knows what she’s doing.
angel_nt/iStock via Getty Images Plus
A house on Mars
Buildings can be 3D printed; initially, they would have to be pressurized and protected until Mars acquired Earth-like temperatures and air. NASA’s Moon-to-Mars Planetary Autonomous Construction Technologies program is researching how to do just that.
There are many other challenges. For example, unlike Earth, Mars does not have a magnetosphere, which protects a planet from the solar wind and cosmic radiation. Without a magnetic field, too much radiation passes through for living things to stay healthy. There are ways to create a magnetic field, but so far the science is very speculative.
In fact, all of the technologies I have described are far beyond current capabilities on the scale needed to terraform Mars. Developing them would require vast amounts of research and money, perhaps much more than is possible in the near term. Although the Genesis device from “Star Trek III” could terraform a planet in minutes, terraforming Mars would take centuries or even millennia.
And there are many ethical questions to resolve before humans can start turning Mars into another Earth. Is it right to make such drastic permanent changes to another planet?
If all this leaves you disappointed, don’t be. As scientists create innovations to terraform Mars, we’ll also use them to make life better on Earth. Remember the technology we’re developing to 3D print habitats on Mars? Right now, I’m part of a group of scientists and engineers using the same technology to print houses here on Earth – which will help address the world’s housing shortage.
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