Could This Fungus Live On Mars? Maybe It Already Does

Could this fungus unrecorded connected Mars? Maybe it already does

An almost unkillable fungal strain isolated from NASA’s ultrasterile cleanable rooms hints astatine “critical gaps” successful interplanetary quarantine

By Leonard David edited by Lee Billings

This selfie-style composite image from May 10, 2025 shows NASA’s Perseverance rover connected nan aboveground of Mars. Within cleanable rooms wherever Perseverance and different spacecraft were tested and assembled, scientists person discovered highly reliable microbes that mightiness past a voyage to Mars—and moreover nan dispute conditions connected nan planet’s surface.

NASA/JPL-Caltech/MSSS

The top pitfall successful nan hunt for extraterrestrial life—according to subject fiction, anyway—is foolhardy researchers someway bringing aliens to Earth to wreak havoc.

But aft decades of exploring our seemingly sterile star system, real-world scientists coming are overmuch much concerned pinch nan other problem: The anticipation that Earth’s life will flight our satellite to contaminate different worlds, sabotaging nan quest to find immoderate genuine “second genesis” of biology astir nan sun. Imagine that a multibillion-dollar robotic ngo recovered wriggling microbes connected Mars and that follow-up studies past revealing those “aliens” had DNA and different biomolecular machinery that showed they were emigrants from Earth.

Astrobiologically speaking, we would person met nan enemy—and it would beryllium us. Taking a cue from sci-fi, you mightiness telephone specified life-forms “Klingons,” for their presumptive hitchhike to nan Red Planet arsenic stowaways successful spacecraft sent from Earth.

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“Planetary protection” is nan word scientists usage for efforts to forestall otherworldly invasions of each sorts; to date, astir of it has focused connected Mars, but nan believe applies to each perchance habitable environments wrong scope of our spacecraft. In nan 1970s, for example, NASA did its champion to support its twin Viking landers Klingon-free earlier launching them to Mars. And if nan NASA-led world Mars Sample Return effort ever manages to bring its precious payload backmost to Earth, nan agency will beryllium tasked pinch quarantining those specimens arsenic if they incorporate extreme biohazards alternatively than lifeless bits of stone and soil.

So far, bacteria person been nan bogeymen that astir planetary protection protocols person been designed to defeat. Now, however, it appears that there’s different type of terrestrial life to beryllium worried about.

A caller study has recovered astir 2 twelve fungal strains isolated from NASA spacecraft assembly cleanable rooms that are tin of surviving a pretakeoff cleansing of ultraviolet radiation exposure. One successful particular—a fungus called Aspergillus calidoustus—proved exceptionally resilient, surviving extended exposures not only to ultraviolet irradiation but besides to conditions mimicking nan vacuum of abstraction and nan aboveground of Mars. A. calidoustus moreover withstood nan baking astatine 125 degrees Celsius that NASA now uses to notionally sterilize spacecraft destined for nan aboveground of that world.

The results, published past period successful nan diary Applied and Environmental Microbiology, propose that NASA, different abstraction agencies and moreover backstage aerospace companies must revise cleanable room protocols to reside nigh-unkillable fungi and bacterial brethren alike. The findings besides raise nan distant but alarming imaginable that erstwhile missions person already exported hardy Earthly microbes to Mars.

An “Entirely Predictable” Critical Gap

The hyper-resilience of A. calidoustus and different fungi correspond a “critical gap” successful planetary protection strategies, says nan study’s lead writer Atul Chander, a postdoctoral microbiologist astatine nan University of Mississippi.

The request to adjacent that spread is increasing much urgent, acknowledgment to a caller procreation of eager missions that purpose to nonstop much landers, rovers and moreover helicopters to Mars—and beyond. It’s besides increasing much complicated, acknowledgment to nan expanding database of nations—as good arsenic private companies—that are readying interplanetary missions, immoderate of which impact returning extraterrestrial samples to Earth.

This overhead position from November 2019 shows NASA’s Perseverance rover (above center) successful nan High Bay 1 cleanable room of nan Spacecraft Assembly Facility astatine NASA’s Jet Propulsion Laboratory.

NASA/JPL-Caltech

Planetary protection policies are coordinated astatine an world level done nan Committee connected Space Research (COSPAR), which provides guidelines to support compliance pinch nan United Nations’ Outer Space Treaty of 1967.

“These guidelines are not circumstantial to immoderate azygous state but are intended to beryllium followed by each spacefaring nations,” Chander says. Indeed, awesome abstraction agencies participate successful COSPAR’s Panel connected Planetary Protection and lend to nan improvement and chat of these standards. Signatory nations are besides responsible for ensuring that backstage abstraction missions that are nether their emblem abide by COSPAR’s policies.

NASA already has a rich | group of COSPAR-compliant procedures, handbooks and training courses to thief guideline its projects, notes Moogega Cooper, a planetary protection technologist astatine NASA’s Jet Propulsion Laboratory successful California. And nan abstraction agency is besides seeking to grow that support, she adds, by processing “more tools” for usage by nan commercialized abstraction community.

According to Nick Benardini, NASA’s planetary protection serviceman astatine its office successful Washington, D.C., immoderate of those emerging devices will beryllium informed by “metagenomics”—the appraisal of communities of microbial organisms straight successful their earthy environments. Such an attack could impact amended search of microbial ecosystems wrong cleanable rooms, supplementing nan abstraction agency’s preexisting bacteria-focused “standard assay” appraisals. Metagenomic mapping of microbiomes successful crewed spacecraft could besides beryllium important successful crafting planetary-protection protocols for immoderate eventual human missions to Mars, Benardini says.

Cassie Conley, who was formerly a NASA planetary protection serviceman from 2006 to 2017, says nan results reported by Chander and his colleagues are wholly predictable and rather efficaciously show nan request for protections successful nan first place.

“The full constituent [is] that we don’t cognize each nan capabilities of life connected Earth—and shouldn’t dress we do,” she says.

The existent astonishment isn’t really definite fungi tin past harsh extraterrestrial conditions, she adds, but alternatively really agelong a simplified bacteria-focused attack has prevailed astatine NASA and different abstraction agencies. That erstwhile reasoning “was only by group who wished that Mars conditions would beryllium sterilizing,” Conley says, “so they wouldn’t person to do planetary protection.... Most extremophile biologists who walk 2 seconds reasoning astir it would beryllium beautiful judge that Earth organisms capable to past connected Mars do exist.”