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Could we one day make Mars like Earth? – Tayla, 16, Mississippi
When I was in middle 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 film, my teacher asked us to write an essay on such technology. Was it realistic? Was it ethical? And to channel our inner spook: Was it logical? This assignment had a profound effect on me.
Fast forward to today, I am an engineer and professor developing technologies to extend human presence beyond Earth.
For example: I’m working on advanced propulsion systems to take spacecraft beyond Earth orbit. I’m helping to develop lunar construction technology to support NASA’s goal of a long-term human presence on the moon. And I’ve been on a team that has demonstrated how to 3D print habitats on Mars.
It takes a lot of time, energy and imagination to sustain humans off Earth. But engineers and scientists have begun to squeeze out the many challenges.
NASA/JPL-Caltech
A partial checklist: food, water, shelter, air
After the moon, the next logical place for humans to live outside of Earth is Mars.
But could Mars be terraformed – i.e. changed to resemble Earth and support life? Or is that just science fiction musings?
To survive on Mars, humans would need liquid water, food, shelter, and an atmosphere with enough oxygen to breathe and thick enough to retain heat and protect it from the sun’s rays.
But Mars’ atmosphere is almost all carbon dioxide, with virtually no oxygen. And it’s very thin – only about 1% of Earth’s density.
The denser an atmosphere, the less heat it can hold. Earth’s atmosphere is thick enough to retain enough heat to sustain life due to what is known as the greenhouse effect.
On Mars, however, the atmosphere is so thin 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 currently has no active volcanoes – at least as far as we know – scientists can trigger volcanic eruptions through nuclear explosions. Gases trapped in the depths of a volcano would be released and then enter the atmosphere. But that plan is a bit of a harebrain, because the explosions release deadly radioactive material into the air as well.
A better idea: redirecting water-rich comets and asteroids to fall on Mars. That would release the gas beneath the planet’s surface into the atmosphere while releasing the water found in the comets. NASA has already shown that small stars can be reoriented – but relatively large ones, and lots of them, are needed to make a difference.
Making Mars peaceful
There are many ways to heat the planet. For example, giant mirrors built in space and placed in orbit around Mars can reflect sunlight to the surface and heat it up.
A recent study suggested that Martian colonists could spread airgel, an ultralight solid, on Earth. The airgel acts as insulation and traps heat. This can be done all over Mars, including the polar ice caps, where airgel can melt existing ice and create liquid water.
You need soil to grow food. On Earth, soil is composed of five components: minerals, organic matter, living organisms, gases, and water.
But Mars is covered in a blanket of loose, dusty material called regolith. Think of it as sand from Mars. Regolith is low in nutrients, not enough for healthy plant growth, and hosts some nasty chemicals called perchlorates, which are used on the ground in fireworks and explosives.
Cleaning the regolith and turning it into something viable won’t be easy. What the alien soil needs is some Martian fertilizer, perhaps made by adding extremes to it – potent microbes imported from Earth that can survive even the harshest conditions. Genetically engineered organisms are also a possibility.
Through photosynthesis, these organisms would begin to convert carbon dioxide into oxygen. Eventually, as Mars became more friendly to Earth-like organisms, colonists were able to introduce more complex plants and even animals.
Providing oxygen, water, and food at the right rates is extraordinarily complex. On Earth, scientists have tried to simulate this in Biosphere 2, a closed ecosystem with ocean, tropical and desert habitats. Although all of Biosphere 2’s environments are controlled, even there scientists struggle to get the balance right. Mother Nature really knows what she is doing.
angel_nt/iStock via Getty Images Plus
A house on Mars
Buildings can be 3D printed; First, they will need to be pressurized and maintained until Mars achieves Earth-like temperatures and air. NASA’s Moon to Mars Autonomous Building Technology program is investigating how to do exactly this.
There are many other challenges. For example, unlike Earth, Mars has no magnetosphere, which protects a planet from solar winds and cosmic rays. Without a magnetic field, too much radiation gets through to keep organisms healthy. There are ways to create a magnetic field, but so far the science is pretty speculative.
In fact, all of the technologies I have described far exceed current capabilities on the scale required to terraform Mars. Developing them will take a huge amount of research and money, probably much more than will be possible in the near term. Although the Genesis machine in “Star Trek III” can terraform a planet in minutes, terraforming Mars takes centuries or even thousands of years.
And there are a lot of ethical questions that have to be addressed before humans start turning Mars into another Earth. Is it right to make such drastic permanent changes on another planet?
If this all disappoints you, don’t. As scientists create inventions to terraform Mars, we use them to improve life on Earth. Remember the technology we’re developing to print 3D habitats on Mars? Currently, I’m part of a team of scientists and engineers who are using that same technology to print homes here on Earth – which will help solve the world’s housing shortage.
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