Astronaut Shubhanshu Shukla's Mars Research: First PLOS One Paper on Bacteria Bricks for Habitats

🚀 Astronaut Shubhanshu Shukla's Groundbreaking Leap from Space to Science

Group Captain Shubhanshu Shukla, India's trailblazing astronaut who made history as the first Indian to visit the International Space Station (ISS) in 2025, has now turned his gaze toward the Red Planet. While pursuing a Master of Engineering in aerospace engineering at the prestigious Indian Institute of Science (IISc) in Bengaluru, Shukla co-authored his first peer-reviewed research paper published in the renowned open-access journal PLOS One on January 29, 2026. Titled "Effect of perchlorate on biocementation capable bacteria and Martian bricks," the study explores a revolutionary approach to constructing habitats on Mars using bacteria sourced from Bengaluru soil. This innovation addresses one of the biggest hurdles in deep-space exploration: building sustainable infrastructure with local resources, known as In-Situ Resource Utilization (ISRU).

The paper, led by Swati Dubey with contributions from Shukla, Nitin Gupta, Rashmi Dixit, Punyasloke Bhadury, and corresponding author Aloke Kumar from IISc's Department of Mechanical Engineering, demonstrates how Earth microbes can transform toxic Martian regolith into sturdy bricks. This fusion of astronaut experience and academic rigor positions Shukla as a pivotal figure bridging India's military aviation, spaceflight, and higher education research ecosystems.

From Fighter Pilot to ISS Pioneer: Shubhanshu Shukla's Journey

Born on October 10, 1985, in Lucknow, Uttar Pradesh, Shubhanshu Shukla grew up in a middle-class family, attending City Montessori School before earning a Bachelor of Science in computer science from Jawaharlal Nehru University. Inspired by the Kargil War, he joined the National Defence Academy and was commissioned into the Indian Air Force (IAF) as a flying officer in 2006. With over 2,000 hours of flight time on advanced aircraft like the Su-30MKI, MiG-21, and Jaguar, Shukla rose to Group Captain, earning the prestigious Ashoka Chakra in 2026 for his contributions to space exploration.

Selected for ISRO's Gaganyaan program in 2019, Shukla trained at Russia's Yuri Gagarin Cosmonaut Training Center and ISRO's Bengaluru facility. In June 2025, he piloted Axiom Mission 4 (Ax-4), spending nearly three weeks on the ISS conducting 60 experiments, including ISRO-led microgravity studies on plant growth and fluid dynamics. Returning to Earth, he seamlessly transitioned to IISc, where his master's research under Aloke Kumar delves into extraterrestrial construction challenges. This paper marks a milestone, showcasing how higher education institutions like IISc foster astronaut-scientists for India's ambitious space ambitions. For aspiring researchers, opportunities abound in higher ed research jobs at premier institutes.

The Science of Biocementation: Turning Soil into Space Bricks

At the heart of Shukla's research is Microbially Induced Calcite Precipitation (MICP), a bioengineering process where bacteria produce calcite (calcium carbonate, CaCO₃) to bind loose soil particles into solid structures. Unlike traditional cement, which requires high heat and energy, MICP operates at ambient temperatures, making it ideal for resource-scarce environments like Mars.

Step-by-step, the process unfolds as follows:

• Bacterial Activation: Urea-hydrolyzing bacteria like Sporosarcina pasteurii break down urea (CO(NH₂)₂) into ammonia (NH₃) and carbonic acid (H₂CO₃) via the enzyme urease.
• pH Shift and Mineralization: Ammonia raises the pH, allowing calcium ions (Ca²⁺) from added calcium chloride (CaCl₂) to react with carbonate ions (CO₃²⁻) from carbonic acid, forming insoluble calcite crystals.
• Binding Regolith: These crystals precipitate around soil grains, cementing them into bricks strong enough for habitats or landing pads.

The team isolated a robust strain, SI_IISc_isolate—phylogenetically closest to S. pasteurii—from Bengaluru soil in 2021. Its genome (3.69 Mb) includes genes for urease (ureC) and perchlorate reduction, hinting at natural resilience.

Mars' Toxic Secret: The Perchlorate Challenge

Martian regolith, the loose, dusty surface soil, poses formidable obstacles. Composed of basaltic fines, iron oxides, and notably 0.5–1% perchlorate (ClO₄⁻ salts like Mg(ClO₄)₂), it is toxic to most Earth life. Perchlorate disrupts microbial metabolism, inhibits photosynthesis, and even explodes when heated, complicating ISRU.

Prior studies showed MICP works on perchlorate-free simulants like Mars Global Simulant-1 (MGS-1), but real Mars conditions demanded testing. Shukla's team simulated 1% perchlorate in MGS-1 to mimic sites like Gale Crater, where NASA's Perseverance rover confirmed high levels. This Bengaluru-led research fills a critical gap, evaluating both bacterial survival and brick viability under duress.

Photo by Karim Imanuel Fox on Unsplash

Experimental Breakthroughs: Methods and Rigorous Testing

The study employed a multi-pronged approach. Bacteria were screened via phenol red assays for urease activity, confirmed by scanning electron microscopy (SEM) showing floret-like calcite precipitates and X-ray diffraction (XRD) identifying calcite peaks.

Perchlorate stress tests included:

• Growth curves in broth with 0.5–3% perchlorate (minimum inhibitory concentration: 3%).
• Gram-staining and live/dead assays revealing cell shrinkage, clustering, and extracellular matrix (ECM) release.
• SEM imaging of 'microbridges' linking cells to precipitates.

Brick fabrication involved mixing bacterial culture, MGS-1 + 1% perchlorate, urea, CaCl₂, guar gum (a natural adhesive from Indian guar beans), and nickel chloride (urease catalyst). Cubes (19 mm) incubated for 5 days were compression-tested on an Instron machine, yielding surprising results.

Surprising Results: Stronger Bricks from Stressed Bacteria

Perchlorate slowed bacterial growth and induced 'multicellularity-like behavior'—cells clumped, releasing protective ECM proteins that formed nutrient-funneling microbridges. While viability dropped, this stress enhanced mineralization.

Compressive strengths (MPa):

Perchlorate doubled strength with guar gum alone, proving its counterintuitive benefit. As Shukla noted, "The idea is to use what's already there," emphasizing ISRU's potential. Read the full PLOS One paper for data visuals.

Implications for Mars Missions and Global Space Race

This work paves the way for self-sustaining Mars outposts by 2030s, enabling roads, pads, and domes without Earth shipments—slashing costs from billions. NASA's Artemis and SpaceX's Starship could integrate MICP, while India's Chandrayaan and Gaganyaan programs benefit from scalable tech.

Earth applications include eco-friendly construction, disaster-resilient structures, and soil stabilization. For Indian researchers, it highlights IISc-IISER collaborations, spurring research assistant jobs in astrobiology.

India's Rising Star in Space Biotechnology

India's space sector, valued at $8 billion, invests heavily in biotech-ISRU. ISRO's Human Space Flight Centre and IISc lead, with Shukla embodying the synergy. Recent feats like Aditya-L1 and Shukrayaan underscore momentum. Higher education plays key, training via academic CV tips for roles in Indian university jobs.

Stakeholders praise: Aloke Kumar calls it vital for "alien environments," Swati Dubey highlights ECM's role.

Photo by Bioscience Image Library by Fayette Reynolds on Unsplash

Challenges Ahead and Future Horizons

• Scalability: Optimizing additives for 100% regolith.
• Radiation/Cold: Testing extremophile strains.
• Payloads: Microgravity MICP experiments on Gaganyaan.

Shukla's lab eyes gene editing for perchlorate tolerance. Globally, parallels with lunar regolith work signal a bio-construction era.

Career Insights: Join India's Space Research Boom

This paper inspires STEM careers. Explore professor ratings, postdoc positions, and career advice. Institutions like IISc seek talent in aerospace and microbiology—check faculty jobs.

In conclusion, Shukla's PLOS One publication heralds a bacterial revolution for Mars habitats, blending India's higher ed excellence with cosmic ambition. Stay tuned for more breakthroughs.