The Quest for the Red Planet
If our species is ever going to inhabit Mars, we are going to have figure out how to survive using the materials found on the planet. Any serious effort to construct habitable living spaces of significant size would quickly be thwarted if we could only rely on Earthly resources, as the cost of shipping large amounts of materials across the interplanetary divide would be extraordinarily high. So we need to have to figure out how to use what's available on alien worlds.
To that end, researchers for Northwestern University have just taken some steps in the right direction.
Since Mars has an abundant supply of sulfur, the researchers set out to see if they could use this to fashion a building material.
Using molten sulfur and simulated Martian soil, they were able to create a form of sulfur concrete. It comes close to mimicking traditional concrete's strength, and it has the added benefits of quick curing times as well as resistance to low temperatures, salt, and acid.
Oh, and it's also completely recyclable.
As Sindya N. Bhanoo notes in the New York Times, Sulfur has historically been used by ancient peoples as a bonding agent in construction, and in particular, it has been used to bond metal to stone foundations. Perhaps we should be surprised that ancient construction methods might be of use for the first colonists of a new planet.
Issues on an Alien World
However, finding the right building materials is just one of many challenges that would-be colonists would (will?) face. In addition the obvious plethora of technological problems such a grand goal poses, various economic, social, strategic, and biological problems will surely arise.
Perhaps most threatening risks to such a program are the challenges we can't foresee–the "unknown uknowns." Undertaking a project so far outside our normal realm of experience, and outside the location of our evolutionary origins, it may be impossible to predict some of the biggest hurdles.
But until we cross that bridge, scientists will continue to make progress on the steps that we know we need to take before we reach Mars. Each time they do, the Red Planet comes a bit closer to home.