Universe Today by Matt Williams 1/19/2023
NASA and the China National Space Agency (CNSA) plan to mount the first crewed missions to Mars in the next decade. These will commence with a crew launching in 2033, with follow-up missions launching every 26 months to coincide with Mars and Earth being at the closest point in their orbits. These missions will culminate with the creation of outposts that future astronauts will use, possibly leading to permanent habitats. In recent decades, NASA has conducted design studies and competitions (like the 3D-Printed Habitat Challenge) to investigate possible designs and construction methods.
For instance, in the Mars Design Reference Architecture 5.0, NASA describes a “commuter” architecture based on a “centrally located, monolithic habitat” of lightweight inflatable habitats. However, a new proposal envisions the creation of a base using organisms that extract metals from sand and rock (a process known as biomineralization). Rather than hauling construction materials or prefabricated modules aboard a spaceship, astronauts bound for Mars could bring synthetic bacteria cultures that would allow them to grow their habitats from the Red Planet itself.
The concept, known as “Biomineralization-Enabled Self-Growing Building Blocks for Habitat Outfitting on Mars,” was proposed by Dr. Congrui Grace Jin – an assistant professor of Civil and Environmental Engineering at the University of Nebraska-Lincoln. Her proposal was one of several selected by the NASA Innovative Advanced Concepts (NIAC) for Phase I development, which includes a grant of $12,500. This program makes annual solicitations for advanced, innovative, and technically feasible concepts that assist NASA missions and further the agency’s space exploration objectives.
Since the 1990s, several architectures have been drafted for crewed missions to Mars, all of which have emphasized the need for keeping launch mass low. Suggestions for how this could be accomplished include inflatable modules. But as Dr. Jin emphasized in her proposal, the physical structures used to outfit the inflatable modules cannot be carried by a crewed spacecraft and generally require a second vehicle to launch them. This is a logistical challenge for missions and drastically increases launch costs.
Another possibility is to use local resources to reduce the amount of supplies that must be transported – a process known as In-Situ Resource Utilization (ISRU). Examples range from the Mars Direct proposal drafted in 1991 by Dr. Robert Zubrin and colleagues from NASA’s Ames Research Center to NASA’s Journey to Mars program launched in 2010. For missions to Mars, this would include using local regolith to create building materials and water ice for astronaut consumption, irrigation, and to create propellant and oxygen gas.
However, this mission architecture requires equipment (like robotic 3D printers) to be transported to Mars. In addition, many designs for ISRU-3D printed habitats still require inflatable modules, which provide scaffolding for 3D-printed structures. For her proposal, Dr. Jin suggests that rather than shipping prefabricated elements or machinery to Mars, habitats could be realized through in-situ construction using cyanobacteria and fungi as building agents. Universe Today recently interviewed Dr. Jin via Zoom, who explained the road that led to her NIAC proposal:
“In the past few years, I was working on self-healing concrete. So when concrete generates cracks, we use bacteria or fungi to induce the biominerals to heal the cracks. And then we think about other possibilities, like self-growing materials. So one would have soil particles or aggregates, we want to use fungi or bacteria to make them into a cohesive body.”
More:
https://www.universetoday.com/159635/instead-of-building-structures-on-mars-we-could-grow-them-with-the-help-of-bacteria/
