Mars once had a thicker atmosphere, but today the planet's surface is exposed to low pressure, strong temperature swings from around -90 C to 26 C, intense radiation, and a carbon dioxide-dominated atmosphere, all of which make construction and long-term habitation difficult. Any system for building on Mars must cope with these environmental stresses while using locally available materials to limit launch mass from Earth.

The authors look to the earliest life on Earth for inspiration, noting how microorganisms in water bodies helped reshape the planet's environment and created mineral structures such as reefs. They focus on biomineralization, where bacteria, fungi, and microalgae form minerals as part of their metabolism, a process that has modified Earth's landscapes for billions of years and can operate in extreme conditions similar to those expected on Mars.

Using composition data from Mars rovers as a guide, the team evaluates different microbial mineralization pathways that could convert Martian regolith into solid building materials without risking harmful biological contamination of the planet. Among these options, they highlight biocementation, in which microbes generate cement-like calcium carbonate at ambient temperatures, as the most suitable route for producing construction materials on Mars.

Central to the concept is a co-culture of two bacterial species with complementary traits: Sporosarcina pasteurii, known for producing calcium carbonate through ureolysis, and the cyanobacterium Chroococcidiopsis, which tolerates extreme environments including Mars simulators. In this scheme, Chroococcidiopsis releases oxygen, improving local conditions for Sporosarcina pasteurii, while its extracellular polymeric substances provide protection from ultraviolet radiation at the Martian surface.

Sporosarcina pasteurii contributes natural polymers that promote mineral formation and bind particles of regolith, turning loose soil into a consolidated, concrete-like material. The article proposes using this living feedstock, a mixture of Martian regolith and the bacterial co-culture, as an input for 3D printing systems designed to fabricate structural components for future Mars bases.

The authors place this work at the intersection of astrobiology, geochemistry, materials science, construction engineering, and robotics, arguing that such a synergistic system could change how structures are designed and manufactured on Mars. They suggest that combining microbial activity with automated 3D printing could enable scalable, site-adapted construction using Martian resources.

Beyond construction, Chroococcidiopsis's capacity to generate oxygen could support life-support infrastructure for crews living in these habitats. Over longer timescales, the ammonia generated as a metabolic byproduct by Sporosarcina pasteurii could be integrated into closed-loop agricultural systems and might eventually feed into wider terraforming concepts for Mars.

The article also notes that planning for Mars habitats in the 2040s is advancing faster than the Mars sample return program, which continues to face delays and limits direct testing of Mars regolith in laboratories. As agencies develop crewed mission architectures for the 2030s and 2040s, the authors argue that bio-based construction strategies need to be matured in parallel.

From an astrobiology standpoint, researchers still need to determine how such microbial consortia interact with Martian regolith analogs and withstand simulated Martian stress factors. Laboratory regolith simulants offer a way to study co-cultures under Mars-like conditions and to build predictive models for biocementation performance before any in situ trials on the planet.

On the robotics and engineering side, a key challenge is approximating Martian gravity on Earth to validate 3D printing processes and autonomous construction protocols. The authors call for advanced control algorithms and carefully tuned procedures that both improve build efficiency and adjust to the specific mechanical and environmental constraints expected on Mars.

They conclude that although much work remains, each experimental campaign, refined protocol, and successful demonstration of microbial regolith consolidation brings long-duration human presence on Mars closer. In their view, stepwise progress in both biology and robotics will be needed before microbial construction methods can support the first permanent Martian habitats.

Research Report:From Earth to Mars: A Perspective on Exploiting Biomineralization for Martian Construction

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