European Space Agency (ESA) has achieved yet another milestone in its efforts to build human colonies on Moon. The ESA scientists have successfully created 3D printed bricks using simulated moondust and a solar furnace. This advance may pave the way for a possible human settlement on the lunar surface in the furture.
Advenit Makaya, who is overseeing the project for ESA, said the team coocked the simulated lunar material in a solar furnace. "We took simulated lunar material and cooked it in a solar furnace," he said.
He further said that a 3D printer table was used for the experiment and successive 0.1 mm layers of moondust was baked at degrees Celsius.
"This was done on a 3D printer table, to bake successive 0.1 mm layers of moondust at 1000 degrees Celsius. We can complete a 20x10x3 cm brick for building in around five hours," said Makaya.
For the test, the commercially available simulated lunar soil based on terrestrial volcanic material was used as raw material. It was then processed to mimic the composition and grain sizes of genuine moondust.
A high-temperature beam of sunlight is created using the solar furnace in order to melt the soil grains together. The bricks that are created as a result have the equivalent strength of gypsum, the main constituent in many forms of plaster.
"For now this project is a proof of concept, showing that such a lunar construction method is indeed feasible," said Makaya.
A previous lunar 3D printing project of the ESA required a binding salt. But the new technique requires only the 3D printer plus solar concentrator to be conveyed to the Moon.
"For a mission like building a base on the Moon surface, in-situ resource utilisation will certainly be one of the most important enabling technologies," said Tommaso Ghidini, who heads ESA's Materials and Processes.
Martian soil turned into strong bricks:
A recent study published in Scientific Reports revealed that researchers at the University of California at San Diego have discovered that a compound very similar to the soil found on Mars can be turned into an extremely strong, dense rock or brick.
They have said that the process to create the brick is very simple, that is using only compression was required to turn the soil into a rock, without any bake method, chemical or heat.
President Donald Trump’s bill has directed NASA to launch a manned mission to Mars in 2033 and the research, funded by US space agency, follows the bill.
“Near-future exploration to Mars connotes the technology of space construction,” the authors write. “Permanent human settlement on Mars requires infrastructure to sustain habitats and life. A steady supply of structural materials is integral towards this effort.”
To carry out the study, a Martian soil simulant dubbed Mars-1a that has a chemical composition very similar the one found on the planet was used by scientists, who have attempted the same in the past as well.
However, all the attempts made previously required polymers to bound the soil together. But this time, polymers were not required at all.
Mars-1a was encased in a rubber tube and was then compacted under high pressure for a small sample. Compression which was equivalent to a hammer blow was sufficient to turn it into a dense rock.
The rock was stronger than typical steel-reinforced concrete. Further study revealed that compression alone turned the soil into rock. What acted as a bonding agent was the nanoparticle iron oxide, common to Martian soil.
“Martian habitats are ideally constructed using only locally available soils; extant attempts to process structural materials on Mars, however, generally require additives or calcination,” the study says. “In this work we demonstrate that Martian soil simulant Mars-1a can be directly compressed at ambient into a strong solid without additives, highlighting a possible aspect of complete Martian in-situ resource utilization.”
What next?
The scientists now have plans to use the same process to create larger bricks. According to them, if further experiments turn out to be successful, the same technique could be helpful in creating structures on Mars by compacting a layer of soil then placing another layer on top and compacting that—and continuing this process until the structure is complete.
"The people who will go to Mars will be incredibly brave,” Qiao said in a statement. “They will be pioneers. And I would be honored to be their brick maker.”
NASA’s hope of human settlement on Mars
NASA is exploring all the options that could pave the way for sending first humans to Mars by the 2030s. It is currently working on the development of Orion spacecraft, which the US agency plans to use to send humans on Mars.
Once the Orion aircraft passes all the safety tests, NASA will send astronauts into space to a distance never covered by humans ever. Eventually, astronauts will then be sent to low-Mars orbit.
NASA also has plans to build a research and operations “outpost” on the surface of Mars. However, getting the material needed to construct permanent structures on the red planet will be a challenge, especially if they have to be transported from Earth.