Resilient Aspergillus Fungus Survives Mars Conditions and NASA Cleanrooms

Scientists have uncovered a fungus capable of surviving the journey to Mars. Researchers tested microbial strains against the brutal conditions of space travel and the Martian surface. Freezing temperatures, ultraviolet rays, ionizing radiation, and low atmospheric pressure usually kill most life forms. However, spores from the fungus *Aspergillus calidoustus* endured these extreme tests.

This pathogen creates grey and brown mould and resists many drugs. It can cause rare, severe, and often fatal infections in immunocompromised people, such as transplant patients. The discovery suggests this unwanted hitchhiker could travel to other planets and become an invasive species. Remarkably, the spores passed through NASA's ultra-sanitized cleanrooms without incident.

Cleaning hardware is a standard strategy to limit Earth microbes traveling to other worlds. Experts work in these sterile facilities to prevent contamination before spacecraft launches. Yet, this study marks the first time scientists showed microbes could persist through every phase of a Mars mission.

The team gathered fungal microbes directly from NASA's cleanrooms. These highly controlled spaces are designed to stop unwanted hitchhikers during spacecraft assembly and testing. The researchers generated conidia, or asexual reproductive spores, from twenty-seven different fungal strains. These samples came from facilities used for the Mars 2020 program, which delivered the Perseverance rover to the Red Planet.

Scientists subjected the conidia to intense simulations of space conditions and the dusty Martian landscape. The spores of *A. calidoustus* tolerated the harsh trials while other strains failed. Study leader Kasthuri Venkateswaran from NASA's Jet Propulsion Laboratory offered a crucial perspective.

"This does not mean contamination of Mars is likely, but it helps us better quantify potential microbial survival risks," Venkateswaran stated. The findings underscore the need for improved planetary protection measures as humanity looks further into the solar system.

Microorganisms display remarkable resilience against harsh environmental conditions. Researchers discovered that only a specific mix of extreme cold and high radiation could finally kill the fungus. Dr. Venkateswaran explained that microbial survival does not rely on a single stressor but on complex combinations of tolerance mechanisms.

The study, recently published in Applied and Environmental Microbiology, expands on earlier findings of bacteria and fungi living on NASA spacecraft surfaces after cleaning attempts. Dr. Venkateswaran noted that these investigations help refine planetary protection strategies for current and future space missions.

Bringing Earth microbes to Mars carries a major risk: they could be mistaken for alien lifeforms, potentially ruining decades of research. There are also fears that tiny organisms might colonize life-support equipment, causing failures in critical life-or-death situations.

Christopher Mason, a geneticist at Weill Cornell Medicine, has warned about the dangers of transporting microbes to other planets. He stated it is vital to protect any existing extraterrestrial life, as new organisms can cause havoc in unfamiliar ecosystems.

Scientists recently found dozens of tiny living organisms inside the Kennedy Space Center cleanrooms in Florida. These were all previously unknown bacterial species. Alexandre Rosado, a bioscience professor at King Abdullah University of Science and Technology in Saudi Arabia, called the discovery a genuine moment to stop and re-check everything.

Analysis of these microbes revealed how they thrive in one of Earth's harshest man-made environments. They possess specific genes that help them resist radiation damage and repair their own DNA.