Scientists find spores survive ISS

Fungal spores are basically nature’s tiny survival capsules, and a new space-exposure paper says some of them are even tougher than people expected. The study, published March 26, put spo(link.springer.com) for 961 days and then checked what was still alive when the samples came back. Most survived. A couple did much better than that. And the weird part is that some space-exposed spores ended up more viable than the same spores left sitting in a lab on Earth. (link.springer.com) ### What actually sat outside the ISS? This was not a fungus growi(link.springer.com)i use to wait out bad conditions. The samples sat on the ISS exterior in near-Earth space, where they saw vacuum from 10⁻⁷ to 10⁻⁴ pascals, about 750 mGy of cosmic radiation, and temperatures swinging from −7°C to 87.5°C over the full exposure period. One important catch — direct solar ultraviolet was shielded by the hardware in this experiment. (link.springer.com) ### Which spores held up best? The paper’s strongest survivors were *Aspergillus piperis* and *Al(link.springer.com)day stint. The same strains stored on Earth for the same period did much worse — almost threefold lower for *A. piperis* and eightfold lower for *A. alternata*. That is the result people are reacting to, because it turns “some survival” into “survival at surprisingly useful levels.” (link.springer.com) ### Why would space preserve anything? Turns out vacuum can work like a brutal freezer-dryer. The authors argue that dehydration i(link.springer.com)es already start with a good toolkit for this — thick cell walls, chemical pigments, low activity, and a built-in ability to sit dormant for long stretches. Earlier work on *Aspergillus niger*, another common ISS contaminant, tied that kind of resilience to pigmented spores with thick walls and strong radiation tolerance. (link.springer.com) ### So did they survive “everything”? Not quite. (link.springer.com)nvironment, but not the full worst-case version of open interplanetary travel, because solar UV was blocked in this setup. That matters a lot. Unfiltered ultraviolet is one of the fastest ways to wreck exposed cells and spores, and earlier ISS exposure work has treated UV as a make-or-break variable. (link.springer.com) ### Does this prove panspermia? No — but it gives the idea a firmer edge. Panspermia is the notion that life, or at least hardy biological material, mig(link.springer.com)ee years in near-Earth space under partial shielding. That does not prove they could survive launch, deep-space transit, atmospheric entry, and landing on another planet. But it does narrow one objection — that eukaryotic spores would simply die too fast in space to matter. (link.springer.com) ### Why are Mars planners paying attention? Because the more durable Earth m(link.springer.com) that microorganisms can survive the station’s extreme environment and keep reproducing. A 2024 *Scientific Reports* paper also found fungi, bacteria, and archaea surviving two years near the ISS, with some fungal strains showing increased radiation resistance afterward. If spores can hitchhike through missions and stay viable, contamination stops being a theoretical paperwork problem. (nasa.gov) ### What’s the real bottom line? The (link.springer.com)sting: dormant fungal spores can remain alive for 961 days outside the ISS, and in some cases space-style dehydration preserved them better than lab storage did. That makes the biology more plausible, the contamination risk more concrete, and the old panspermia debate a little less hand-wavy. (link.springer.com)