The Impact of the Space Environment on Microbial Growth and Behavior

Book excerpt: Microorganisms play an important role in life on Earth and can adapt and survive in harsh and changing environments. Their aptitude to thrive under hostile conditions is reflected by their survival and activity in some of the most extreme environments on Earth and their presence and growth in low earth orbit and outer space. Spaceflight and the space environment have a unique set of stressors compared to Earth (microgravity, galactic cosmic radiation, solar UV radiation, space vacuum, thermal extremes) that microbes are exposed to, but how they adapt and respond is still poorly understood. Studies to date, though, have shown that these responses can range from being beneficial for human exploration to negatively impact long duration missions. Hence, investigating the reaction of microorganisms to space conditions, the alterations in their physiology and virulence, not only helps shed light on the molecular basis of tolerance, but has implications for both space exploration and astrobiological missions.