Space microbiology studies how microorganisms adapt and survive in extreme space conditions such as

microgravity, radiation, and vacuum. As space missions extend to the Moon, Mars, and beyond, understanding

and oxygen production. Effective microbial management is vital for sustaining long-term space missions. This

review underscores the importance of space microbiology in ensuring safe, sustainable space exploration and

advancing the search for life beyond Earth.

Keywords: Microbial adaptation, Microbial contamination, Microbial behaviour in space, Space biology.

Space microbiology is the study of how microorganisms respond to the extreme conditions of space, such as

microgravity, radiation, and the vacuum. As we explore longer-duration space missions, such as those to Mars,

the Moon, or beyond, understanding how life survives and adapts to space is crucial for astronaut health and the

sustainability of human space exploration. Microorganisms are among the most resilient forms of life, capable

of thriving in some of Earth’s harshest environments, such as hydrothermal vents and polar ice caps

Microgravity disrupts these processes, leading to slower or accelerated growth in various microbial species

(Zabel et al., 2009). For example, some microbes may replicate more rapidly in microgravity due to changes in

fluid dynamics and nutrient diffusion, while others adapt by forming biofilms. These biofilms offer protection,

enabling microorganisms to maintain stability in the absence of gravitational forces (Fujimura et al., 2015).

Biofilms are microbial communities encased in extracellular polymeric substances (EPS), which help microbes

maintain their structure and resistance to environmental stressors. In space, biofilms appear to be more resilient

than those formed on Earth, highlighting the adaptability of microorganisms to hostile conditions (Krasny et al.,

2017). Additionally, space-adapted microbes can alter their morphology by shifting from spherical to elongated

shapes, enhancing their nutrient absorption and attachment to surfaces (Yamaguchi et al., 2018).

technologies, critical for astronaut safety during space missions (Nichols et al., 2009). The study of radiation-

resistant microbes also holds implications for astrobiology. If microorganisms can survive extreme radiation

levels in space, they may also be capable of thriving on other planets or moons with harsh conditions, such as

Mars or Europa (Cockell et al., 2000). This supports the hypothesis that life may exist beyond Earth in

environments that were once thought to be too extreme.

Spacecraft, especially those on long-duration missions, act as closed ecosystems where microbial populations

evolve in isolation from Earth-based influences. Microbes aboard spacecraft colonize various surfaces such as

walls, air filters, and crew members' skin and clothing. Environmental factors like temperature, humidity, and

air circulation influence microbial behavior and community composition, while human activities, including

The need for effective microbial control strategies to ensure astronaut health and spacecraft functionality is

evident. However, microbial communities can also benefit life support systems. In closed-loop environments,

microbes recycle waste, purify water, and generate oxygen—essential processes for long-duration space

missions (Bailo et al., 2017). Photosynthetic microbes, such as cyanobacteria, could help convert carbon dioxide

into oxygen, providing a sustainable source of breathable air for astronauts (Rummel et al., 2014). Additionally,

microorganisms that are used in Earth-based systems for wastewater treatment and bioremediation could be

adapted for resource recycling and sustainability in space (Lund et al., 2019). Given the potential risks and

benefits, managing microbial populations aboard spacecraft is vital for maintaining astronaut health and mission

success. While microbial presence on spacecraft is inevitable, understanding how space conditions—such as

air and water quality, posing health risks such as infections or allergic reactions, and may degrade life support

systems. Therefore, rigorous hygiene protocols, antimicrobial coatings, and advanced sterilization methods are

essential for preventing microbial contamination and maintaining the integrity of spacecraft systems (Davila et

al., 2019). Microbes’ ability to thrive in space also opens up new possibilities for sustainable human exploration.

By harnessing microbial processes, such as waste recycling and oxygen production, we can reduce the need for

resupply missions and support closed-loop life support systems. Space microbiology not only helps ensure

astronaut safety but also contributes to developing biotechnologies that may allow humans to live and work in

space for extended periods.

Space microbiology plays a pivotal role in advancing human space exploration by shedding light on how

microorganisms adapt and survive in the extreme conditions of space. As we embark on longer missions to the

resilience and its applications in future space exploration and the search for extraterrestrial life. Ultimately, space

microbiology is integral to the sustainable and safe expansion of human presence in space.