Are there bricks on Mars?
A manned mission to Mars may not need to transport building materials from earth, as Ellis Davies reports.
With a 2033 date planned for a manned mission to Mars, scientists are examining materials and methods for building habitats on the red planet. A team from the University of California San Diego, USA, funded by NASA, has developed a potential solution that would use martian soil and pressure to create bricks.
Other methods incorporating martian soil have previously been suggested, including the use of nuclear-powered brick kilns or the transformation of soil into binding polymers through complex chemistry. The solution discovered by the team was the result of experiments cutting down the amount of polymer required to shape the soil into bricks – they discovered that none was needed.
To manufacture a martian brick, the Mars soil simulant is placed into a flexible container, such as a rubber tube, and pressure is applied. A small sample requires roughly the equivalent pressure created by dropping a 4.5kg hammer from a height of one metre. This method produces small round soil pallets, around 2.5cm tall, which can be cut into brick shapes.
The team believes that the iron oxide in the soil acts as a binding agent, as it has clean flat facets that can easily bind together under pressure. The strength of the bricks was also investigated, and the team claims that, even without rebar, the bricks are stronger than steel-reinforced concrete.
The method could present a simple, effective solution to the building of structures on Mars, with astronauts needing only to put down a layer of soil, compact it, and repeat. The next step for the research group will be to increase the size of the bricks.