Image Source Have you ever heard of stories claiming the construction of colonies and buildings on planet Mars? It does spark hope in many that someday they’re going to travel to Mars. Well soon, it’s going to be a thing of reality!
With the growing interest of sending humans to planet Mars, space agencies have begun researching ways to send them safely. But what about high-quality living? Even if they take temporary structures with them, it’s not a permanent solution.
We will surely need concrete to construct habitats as it’s been significant in the colonization of our planet. The Pantheon and Colosseum in the Roman empire and Egyptians too built their colonies using concrete. And, today we’re producing two billion tons of concrete every year.
Looking at the current need, scientists had to take their concrete vision to outer limits. Thus, the gap between the dream of sending humans to Mars and the reality of actually accomplishing it seems to contract with new possibilities.
We can say that we’ve finally got a solution for colonization and settlement on Mars. Lin Wan and his team at Northwestern University developed a strong sulfur concrete that can be used to build habitats on Mars. They heated sulfur to 240 degrees Celsius, liquefied it, and determined it would be usable. However, there are a lot of challenges and issues that would come their way. The journey would be troublesome, but we hope the result will be fruitful. Let’s explore different aspects of Martian concrete and the challenges that come along.
WHAT IS MARTIAN CONCRETE?
Martin concrete is a formulation that combines Martian soil with molten sulfur, which could be the key feature of human colonization on the planet Mars.
What’s so intriguing about Martin Concrete?
As we know, there is a scarce supply of water on Mars. Why? The majority of water that exists on Mars is frozen today. Most importantly, unlike regular concrete that we currently use for construction, Martin Concrete is produced without water.
In addition to this, the material is entirely recyclable. What’s the benefit for us? It could be melted down and reset into a new form. Moreover, it has a natural resistance to acid and salt, which means it can endure very low temperatures.
"Due to the dry environment on Mars, sulfur concrete concept is a superior choice for building a human village on the red planet," Claims team reports.
They further added, "Moreover, the atmospheric pressure as well as temperature range are highly suitable for the application of sulfur concrete."
CONSTRUCTION ON EARTH IS DIFFERENT AND CHALLENGING THAN ON MARS - KNOW WHY
On Earth, concrete is a composite material, which is made up of multiple ingredients. The usage of multiple materials is called an aggregate. This aggregate includes the following: limestone, granite, sand, and other crushed rocks. All these materials are bonded together with cement to make the final concrete used for construction.
People are often confused with two words “cement” and “concrete.” They often use these two words as synonyms for one another, but there is a difference. Chemically, water is the cementing agent that holds the concrete together. When concrete is mixed with water, it forms a hard, durable, solid matrix when it dries. It becomes malleable, and this is the reason that it can be given various shapes and forms, without cracking or breaking it.
But, when it comes to construction on Mars, water is the big issue in the process. Here sulfur is the main part. Fortunately, Mars contains tons of sulfur, it’s around 17% of the planet’s makeup. Thus, we can say that the aggregate part of Martian concrete is easy enough to find there.
The abundance of sulfur on Mars is the reason Northwestern's researchers think that sulfur is going to be the key to construction on Mars. However, this is not the first time there’s been buzz about sulfur-based concrete, researchers tried it in the 1970’s. The material scientists explored the possibility of sulfur concrete to build bases on the moon.
But there was an issue with this idea. Sulfur didn’t become a liquid; instead, it went straight from solid to gas due to the vacuum. This is the reason that construction is not possible without an atmosphere.
"In the almost vacuum condition of the moon, the sulfur disappears," says, Gianluca Cusatis, Ph.D., M.ASCE, an associate professor in the Department of Civil and Environmental Engineering at Northwestern and the lead researcher on the team. "In the earlier work they showed that when they put [the] material in a vacuum, after a few months—or even earlier—the material is not there anymore because all the sulfur would disappear."
This process is called sublimation.
But here’s the ray of hope!
Mars is not a vacuum like a moon. The atmospheric pressure on Mars is more similar to Earth, so the sulfur concrete would not be subject to sublimation on Mars. Thus, it won’t turn out to be an obstacle.
As the Northwestern team had already discovered, the presence of the atmosphere is sufficient to make sulfur concrete. The researchers were able to build blocks of quasi-Martin concrete by mixing the aggregate 50/50 with molten sulfur. The aggregate consisted mainly of simulated Martian soil consisting of silicon dioxide, aluminum oxide, iron oxide, titanium dioxide. Surprisingly, it turned out to be two-and-a-half times as strong as the concrete commonly used on Earth.
Still, there are challenges. For instance, sulfur can shrink in low temperatures. It impacts the overall strength and durability of any material or structure made from sulfur.
To overcome such issues, the team is experimenting with different concrete including, three-point bending and unconfined compression. They used different percentages of molten sulfur. They carried out a series of tests to determine the strengths and failures of different blends.
In doing so, they found that the material made with a mix of sulfur and aggregate has a strength of 50 megapascals. It equates to 3x as much on Mars due to the difference in gravity, which makes it feasible for construction there.
"The best mix for producing Martian concrete is 50 per cent sulfur and 50 per cent Martian soil with maximum aggregate size of one millimeter," reads the report.
FINAL WORD
With new possibilities, discoveries, and experimentation, the potential to make concrete on Mars without the need to ship the raw material will make it easier and cheaper to build structures on site. We can see that the idea of building a home on Mars is in the not-too-distant future.
We hope you find this informative, if this peaked your interest, stay tuned with us for more such posts!