reliablereason 2 hours ago

I did some basic calculations to compare the energy in the radiation vs the energy required to grow 10% extra.

- If we assume they are working in the reactor we get radiation levels of something like 1 mGy/hour. But we can prop this up to mabye 500 mGy/hour since i dont know how they grew their culture

- That leads to 0.05 J of extra energy per gram of microbial bio material.

- Energy needed to grow 1g of microbial biomaterial ≈ 3.15 kJ 10% of that is 315 J per gram

The result is that:

The amount of radiation energy available is 4 orders of magnitude too small to power even a 10% growth boost.

Edit: updated with more accurate estimations.

  • once_inc an hour ago

    Add in some evolutionary strategies, and you have the recipe for a good sci-fi book: a fungus in Chernobyl rapidly outpaces its competitors due to its ability to absorb radiation. Each iteration grows and reproduces faster, until it is so blindingingly fast that it begins to outpace the output the fuel rods produce.

    The world rejoices as this fungus is perfect for cleaning up nuclear waste products, until we realize that it evolved to function outside of Chernobyl and begins to eat everything it can reach. Mankind launches into a desperate struggle for survival as the fungus lays waste to large swathes of land.

    • Andrex an hour ago

      This lines up with a book idea I've had for like 20 years. Crazy!

      Don't wait to write sci-fi I suppose! Life may catch up, haha.

      • robocat 15 minutes ago

        I'm trying to work out how the fungus evolves to grow its food source by causing radioactivity increase?

        It can concentrate radionuclides, but the step function after inducing some criticality is likely to cause reproductive difficulty (stopping fungus evolution).

        Plus: heavy metals combined with organics have a tendency towards being nasty poisonous

      • rrr_oh_man 18 minutes ago

        Idea is nothing, execution is everything.

        Just write it if you want to.

    • Joel_Mckay 40 minutes ago

      Some fungi are already the largest organisms on earth at >200 km^2

      Armillaria ostoyae ( https://en.wikipedia.org/wiki/Armillaria_ostoyae )

      Consider when organisms must pass, that these ancient fungi likely still consume the host... Thus, on a 8000 year timescale most fungi doesn't necessarily need to pursue food that naturally dies in around a century.

      Yeasts are already sharing your body along with numerous other organisms that are often harmless or even beneficial. Best not think about it too much if you are uncomfortable with seeing yourself as an mini ecosystem. =3

    • throwawaymaths an hour ago

      Aside from the Chernobyl part, that's basically Andromeda strain

  • kalaksi 2 hours ago

    I'm not sure where you're going with this, but since they have actually researched how it grows, I think it's more likely your calculations/assumptions are incomplete.

    For example:

    > Energy needed to grow 1g of microbial biomaterial

    based on what?

    Edit: Maybe you meant that radiation alone wouldn't be enough for that growth, so there'd be other components that it's helping with.

    • reliablereason an hour ago

      Initially i asked a AI for standard values but here is a proper source:

      - Negentropy concept revisited: Standard thermodynamic properties of 16 bacteria, fungi and algae species ( https://arxiv.org/abs/1901.00494)

      > Maybe you meant that radiation alone wouldn't be enough for that growth, so there'd be other components that it's helping with.

      Yes. Clearly it grew as it grew, but the question is what drove/powered the growth.

      • i_cannot_hack 31 minutes ago

        > Initially i asked a AI for standard values

        Don't do this, and don't then share the resulting numbers as fact publicly without disclosing you just asked a chatbot to make up something reasonable sounding.

        If the chatbot refers to a source, read the source yourself and confirm it didn't make it up. If the chatbot did not refer to a source, you cannot be sure it didn't make something up.

        The property measured in the source you linked, "enthalpy of formation", is not the same as the energy required to grow 1g of biomatter. One clue of this is that the number in the paper is negative, which would be very strange in the context you requested (but not in the context of the paper). For the curious: "A negative enthalpy of formation indicates that a compound is more stable than its constituent elements, as the process of forming it from the elements releases energy"

        You're feeding yourself (and others) potentially inaccurate information due to overconfidence in the abilities of LLMs.

  • credit_guy an hour ago

    I also did some back of the envelope calculations. Here's what I got: the radiation level just 1 meter away from the "elephant foot" (the solidified molten core), at the time of the accident was about 1000 times lower than the solar irradiation. At 100 meters it was 10 million times lower (because of the inverse square law). Now, the radiation from the elephant foot has decreased significantly. I couldn't find a recent estimate, but I would expect it to be at least 100 times lower. So at 100 meters from the elephant foot, the radiation level is a billion times lower than what you get from the sun. There's no way any organism can "feed" on that.

  • engine_y 2 hours ago

    There's another parameter worth considering - how efficient is it to convert sunlight vs. gamma radiation into biologically usable energy.

    What if for some reason gamma radiation changes the equilibrium constants for ADP --> ATP?

    • aeonik an hour ago

      Another hypothesis to test would be if the radiation is being used as a catalyst somehow.

      E.g. Could be denaturing something else, unlocking a previously inaccessible energy source. Possibly some radiochemistry creating a new food source for the fungus too.

  • vintermann 2 hours ago

    Yeah, from that it sounds like the main advantage of this mold is that it gets some compensation from all that deadly radiation, and thus does better than mold which doesn't.

mikkupikku an hour ago

I feel like I'm taking crazy pills every time I read about this fungus. Let us grant the premise of a fungus somehow harnessing ionizing radiation using melanin; such a fungus could in principle be used to shield radioactive sources, but it won't "eat it up"; the radioactive isotopes emitting that radiation won't be disposed of in any way by the fungus. They don't eat those, and even if they did it wouldn't get rid of them, only incorporate them. Neither chemical nor any kind of biological process can make radioactive isotopes stop being radioactive, you need some sort of nuclear process to do that. The absolute best the fungus could do is bind up the radioactive isotopes to aid in their collection, but epoxy resins sprayed over the contaminated areas are far more effective than that could ever be.

Also, making spacecraft shielding and even furniture out of this stuff? It's the stupidest thing I ever heard. The mass of the fungus doesn't come from ionizing radiation anymore than the mass of a plant comes from sunlight. You might as well claim that you're going to grow trees in space using the abundant sunlight. They power themselves with light but still need to be made out of something! Are they also hoping these fungus like to eat lunar regolith? It makes zero sense, but here we've got the BBC and apparently NASA taking the idea seriously. Where is the fucking biomass meant to come from?? I must be crazy, or they all are.

  • VladVladikoff an hour ago

    >the radioactive isotopes emitting that radiation won't be disposed of in any way by the fungus. They don't eat those, and even if they did it wouldn't get rid of them

    Please excuse the novice question but I am confused, where does the energy come from then?

    • mikkupikku an hour ago

      Granting the premise, the fungus gets energy (but not mass) from the natural decay of radioactive particles. It doesn't accelerate that decay, the decay happens at the same pace it would have without the fungus. Just like planting more plants doesn't make the sun burn out any faster. The fungus itself is made of carbon and all the other usual stuff life is made from.

  • wongarsu an hour ago

    In regards of NASA taking it seriously, my null hypothesis would be that reporters misunderstand NASA just as much as everything else about fungi.

    If I understand the linked NASA press releases correctly, they are talking about using a mix of regolith, cyanobacteria and fungi as part of the outer shell of a habitat. The mycelian network of the fungi binds the loose regolith together, forming a strong material with strong and somewhat flexible material, with the fungus working a bit like the cement in a concrete mix. And because fungi don't form from nothing you add cyanobacteria that create "fungus food" (presumably some sugar) from water and CO2 (I'm sure you need to add a bit more than that, but that might be beyond the scope of a press release)

    This really has nothing to do with radiation-absorbing fungi at all, except for one remark how the melanin in radiation-eating fungi could provide further shielding.

  • lazide an hour ago

    Something the fungus COULD do (in a hypothetical world) is concentrate radioisotopes along with some moderator to accelerate the fission process and harvest more energy.

    Would probably require a lot more time than it would have, however, considering the relatively low amounts of radioisotopes in todays world (due to the halflife of most of them, and the age of our planet).

    Several billion years ago it could have been a thing though!

    • mikkupikku an hour ago

      Maybe in principle, but neutron radiation from fallout/etc is relatively minimal and you really just have to wait out the decay of those isotopes.

      The good news is radiation detectors are insanely sensitive so you can map where the hotspots are and mitigate much of the risk using exclusion zones and / or various cleanup techniques to collect the radioactive material so it can be safety stored.

mrweasel 2 hours ago

I wonder if you could power something of this? If the fungus have some type of melanin that will turn ionized radiation into energy, could we then use that to power something of background radiation?

Also interesting to see how close this fungi will grow to the radiation source, or will it be able to mutate to completely envelop the radiation source.

  • dodslaser an hour ago

    Just dry the fungus and burn it. The process is fairly analogous to photosynthesis in plants, so we've basically already been doing this since we learned to make fire, just with a different source of radiation.

    • mrweasel 42 minutes ago

      That would be fun on a space craft. Steam power spacecraft, powered by burning mushrooms.

      • ethmarks 27 minutes ago

        And the mushrooms would be powered by cosmic radiation...

  • VladVladikoff an hour ago

    I had the same thought, I wonder if we could make better solar cells?

HelloUsername an hour ago

Related:

"Fungus in Chernobyl nuclear disaster zone has mutated to 'feed' on radiation (2024)" https://news.ycombinator.com/item?id=45901149 12-nov-2025

"Fungus found in Chernobyl might process radiation and act as a shield (2024)" https://news.ycombinator.com/item?id=43534021 31-mar-2025

"A Black Fungus Might Be Healing Chernobyl by Drinking Radiation" https://news.ycombinator.com/item?id=43148355 23-feb-2025

"Radiotrophic fungus" https://news.ycombinator.com/item?id=41085406 03-aug-2024

"Chernobyl fungus could shield astronauts from cosmic radiation" https://news.ycombinator.com/item?id=35181146 16-mar-2023

"Fungus at Chernobyl absorbs nuclear radiation via radiosynthesis" https://news.ycombinator.com/item?id=24166994 15-aug-2020

"Radiotrophic fungus" https://news.ycombinator.com/item?id=20342750 03-jul-2019

"Chernobyl Fungus Feeds On Radiation (2007)" https://news.ycombinator.com/item?id=6763520 19-nov-2013

"Black Fungus Found in Chernobyl Eats Harmful Radiation" https://news.ycombinator.com/item?id=127626 02-mar-2008

_young_grug_ an hour ago

This would be a cool origin story for astrophage (from Project Hail Mary, a fun & light sci fi read by the Martian guy)

  • api 3 minutes ago

    Also this is how the protomolecile from The Expanse feeds. It can absorb pretty much any radiation across the whole spectrum.

  • kakacik an hour ago

    There is a movie coming with Ryan Gosling, I sure hope they keep the spirit of the book and don't turn that into some bizarre hollywoodish cash grab

firesteelrain 2 hours ago

How do you eat something you can’t see? It’s like eating electricity

  • nkrisc 2 hours ago

    Or sunlight.

  • mrweasel 39 minutes ago

    ... I mean, blind people exits. They can't see their food either, but I get where you're going: eating something with no mass.

jansan 2 hours ago

> Zhdanova suspected that the melanin of these fungi was acting as a shield against ionising radiation.

Wouldn't that be very easy to measure? My guts tell me that using the melanin as a shield against gamma radiation has a negligible effect, if any at all.

  • londons_explore an hour ago

    You are assuming a molecule good at shielding against UV light is probably a poor shield against gamma rays, many orders of magnitude shorter wavelength. That sounds probable ...

    But how about the theory that systems to clean up smashed up proteins from UV light is also good to clean up smashed up proteins from gamma radiation?

    And one of the parts of that system, or upregulated with that system, is melanin.