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Is it possible that one day we could 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 depiction of “Project Genesis” – a new technology that transformed a dead alien world into one 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 channeling our inner Spock: Was it logical? This assignment had a huge impact on me.
Fast forward to today and I am an engineer and professor developing technology to extend human presence beyond Earth.
For example: I work on advanced propulsion systems to get spacecraft beyond Earth orbit. I help develop lunar construction technologies that will 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.
Keeping humans off Earth will take a lot of time, energy and imagination. But engineers and scientists began to overcome many challenges.
NASA/JPL-Caltech
Partial checklist: Food, water, shelter, air
After the Moon, the next logical place for human life outside of Earth is Mars.
But is it possible to terraform Mars – that is, transform it to resemble Earth and support life? Or is it just science fiction musings?
To live on Mars, humans will need liquid water, food, shelter, and an atmosphere with enough oxygen to breathe and dense enough to retain heat and protect against radiation from the Sun.
But the Martian atmosphere is almost entirely carbon dioxide, with virtually no oxygen. And it’s very thin – only about 1% as dense as Earth.
The less dense the atmosphere, the less heat it can hold. Earth’s atmosphere is dense enough to retain enough heat to sustain life through what is known as the greenhouse effect.
But on Mars, the atmosphere is so thin that nighttime temperatures routinely drop to 150 degrees below zero Fahrenheit (-101 degrees Celsius).
So what’s the best way to give Mars an atmosphere?
Although Mars now has no active volcanoes—at least as far as we know—scientists could trigger volcanic eruptions through nuclear explosions. Gases trapped deep within the volcano would be released and then released into the atmosphere. But this scheme is a bit hackneyed because the explosions would also send deadly radioactive material into the air.
A better idea: Redirecting water-rich comets and asteroids to hit Mars. This would also release gases from beneath the planet’s surface into the atmosphere while also releasing the water found in comets. NASA has already shown that it is possible to redirect asteroids – but it takes relatively large ones and lots of them 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 could reflect sunlight onto the surface and heat it.
One recent study suggested that colonists on Mars could spread airgel, an ultralight solid material, on the ground. The airgel would act as insulation and retain heat. This could be done all over Mars, including the polar ice caps, where airgel could melt existing ice to create liquid water.
You need land to grow food. 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 is low in 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 viable would not be easy. The alien soil needs some kind of Martian fertilizer, perhaps made by adding extremophiles—hardy microbes imported from Earth that can survive even the harshest conditions. Genetically modified organisms are also an option.
Through photosynthesis, these organisms would begin to convert carbon dioxide into oxygen. Eventually, as Mars became more life-friendly for terrestrial organisms, the colonists were able to introduce more complex plants and even animals.
Providing oxygen, water and food in the right ratio is extremely complex. On Earth, scientists have tried to simulate this in Biosphere 2, a closed ecosystem with oceanic, tropical and desert habitats. Although all of Biosphere 2’s environments are controlled, even there scientists are trying to find the right balance. Mother Nature really knows what she’s doing.
angel_nt/iStock via Getty Images Plus
House on Mars
Buildings could be 3D printed; they would initially have to be pressurized and protected until Mars attains Earth-like temperatures and air. NASA’s Moon-to-Mars Planetary Autonomous Construction Technologies program is investigating how to do exactly that.
The challenge is much more. For example, unlike Earth, Mars does not have a magnetosphere that protects the planet from the solar wind and cosmic rays. Without a magnetic field, too much radiation passes through for living things to stay healthy. There are ways to create a magnetic field, but the science is still very speculative.
In fact, all of the technologies I have described are far beyond current capabilities at the scale required to terraform Mars. Developing them would require a huge amount of research and money, probably much more than is possible in the near future. Although the Genesis device from “Star Trek III” could terraform a planet in minutes, it would take centuries or even millennia to terraform Mars.
And before humans start turning Mars into another Earth, there are many ethical questions to be resolved. Is it right to make such drastic permanent changes on another planet?
If all of this puts you off, don’t be. As scientists create innovations to terraform Mars, we will also use them to improve life 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 who are using the same technology to print houses here on Earth – which will help solve the global housing shortage.
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