[HN Gopher] Self-replicating radiation-shield for deep-space exp... ___________________________________________________________________ Self-replicating radiation-shield for deep-space exploration: Radiotrophic fungi Author : che_shr_cat Score : 154 points Date : 2022-01-15 13:58 UTC (9 hours ago) (HTM) web link (www.biorxiv.org) (TXT) w3m dump (www.biorxiv.org) | choeger wrote: | What is it with all the fuzz a out fungi in space lately? Is | Discovery so well-liked or is it the other way around? | | Serious question: How does the fungus release the energy? heat? | Could we use them as some kind of biological radiation thermal | panels on Mars? | dnautics wrote: | My guess is that the original paper is artefactual, but there's | no reason a priori that an organism _couldn 't_ take large | classes of ionizing radiation and turn it directly into | chemical energy, ionizing radiation, after all, effects | chemical transformations. | nynx wrote: | Clearly the end goal for this research is figuring out why the | fungi can block radiation and taking advantage of that for better | radiation shielding. We're not going to be flying around in | spaceships coated in fungi. | Chris2048 wrote: | Hmm, how would fungi be different from a self-repairing | expanding foam? Other than needing to be kept alive? | xvilka wrote: | Maybe the future of space travel are living spaceships. Some | kind of crustaceans with outer shell, living main body, and | human crew inside. Something between fungi, animal, and plant | even. | jorvi wrote: | > Something between fungi, animal, and plant even. | | You mean a protista? | vbezhenar wrote: | IMO future of everything is replicating nano-robots, | artificial life-like beings. Nature can't be as good as | artificially created specialized mechanisms. Right now nature | have an advantage in self-replicating cells which we can't | reproduce yet, but I'm sure that we will. | edgyquant wrote: | Maybe over 2 billion years nature has created as efficient | as we can get, and it would be best to have hybrid life | that is a mix of nano-tech and biological cells. Is it a | given that we could create tiny factories more efficiently | than cells? | IX-103 wrote: | Nature tends to get stuck in local optimums where things | are "good enough". For reference see the recurrent | laryngeal nerve, the "backwards" eye in many animals | (though not octopuses or their relatives). | | We can do better than nature just by taking the best from | everything, integrating it together, and removing all the | extra junk. Imagine if we just used it as inspiration. | | I'm not saying tiny factories wouldn't end up looking | like cells, but I expect the similarities to be | superficial, as we have access to more robust materials | to serve as feedstock and can have better control of the | operating environment. | walleeee wrote: | cool, like the yuuzhan vong | | in a sense a planet is one of these already, just a little | less maneuverable than we would maybe prefer out of a ship, | and inverts the hard shell soft interior crustacean-ship idea | | for large ships maybe you could literally use a planet, e.g. | swing a spare one out of the solar system in the direction | you want to go... if rogue planets can hold down an | atmosphere and stay geologically active [0] maybe you could | have liquid water oceans and sea life and atlantean cities | scattered around the seafloor drawing hydrothermal power | | plus you're hidden pretty well flying dark in interstellar | space, maybe civilizations deem it prudent to leave their | parent stars for dark forest concerns etc, maybe you could | even harness earthquakes/vulcanism to (very slowly) | manipulate the angular velocity vector enough to course- | correct and navigate | | [0]: https://doi.org/10.1038%2F21811 | f6v wrote: | That's straight out of Farscape, iirc. I remember watching a | living ship fly though space as a kid and it seemed like a | giant stretch. But maybe it isn't. | T-A wrote: | Good old Moya: | | https://farscape.fandom.com/wiki/Moya | edgyquant wrote: | Maybe these competing for resources around stars is the | future of life | FredPret wrote: | > crustacean | | We'll call it the lob-star | arcticbull wrote: | Why _not_ Zoidberg, tbh? | justinator wrote: | I call it: delicious! | whalesalad wrote: | Why not? I mean, the fungi would die out in space without | oxygen but if it retained its properties it could be used just | like any other material: wood, steel, ceramics, etc. | | The coolest part about fungus is that it will grow into its | environment, so I would imagine molds (no pun intended) could | be used to "grow" a panel, sheet, etc almost like natural 3D | printing. | mtsr wrote: | There are a few companies that produce packaging alternatives | for EPS that way. | kortex wrote: | I mean why not? Hard radiation tends to destroy whatever it | hits on a molecular/atomic level. If you have a biological | shield which is constantly refreshing itself, you can possibly | have a much lighter assembly. Mycelium has also been used to | purify water. It might be possible to integrate shielding with | water storage/buffer and recycling. | | It'll probably require layering different types of material to | convert higher energy radiation (like cosmic rays) to more | manageable spectra. | FredPret wrote: | If we had a fungi that could purify water and block out deep | space radiation, that would be one sweet mushroom. | | Better hope it doesn't die halway to Mars! | kortex wrote: | Yeah, that would be something we'd want to do long-scale | simulation tests of before setting sail. Build a simulated | spaceship, probably in orbit for maximum accuracy, and see | how everything holds up. | | Tbh I'd be more concerned about the humans cracking | psychologically before the fungus dying. They are hardy | buggers. | lallysingh wrote: | I think the end goal would be a fungi that we can layer between | hulls and is low maintenance. Or even better, that also | generates oxygen. Maybe even feeds on human waste. | abletonlive wrote: | fungi consume oxygen, or at least, most of them do. not sure | why people think of fungi as plants. | ipodopt wrote: | We don't want a material that builds and repairs itself? | | Anyhow, seems like they think it is the concentration of | melanin in the fungi. The melanin has been sequenced and it is | the same type found in human skin. Maybe we will see this | adaptation in space fairing humans... Wonder if current black | astronauts are less effected by radiation. | | EDIT: Probably something that will seem so obvious in | hindsight. | T-A wrote: | Check out the Martian settlers in Spin: | | https://en.wikipedia.org/wiki/Spin_(novel) | hinkley wrote: | Because fungi are some of the oldest terrestrial organisms on | the planet. Today they often enjoy shade and humidity, but at | the time there was melanin and other UV blocking chemicals, or | wearing other organisms as a hat (lichen). | | There's one interpretation of evolution where fungi are the | original farmers. Everything from lichen up to and including | trees only happening because it suited fungi to do so. | MertsA wrote: | I don't understand the interest here. It's not like fungi are | magically more effective than virtually any other mass at | absorbing ionizing radiation and subatomic particles. "Self- | replicating" is meaningless when it needs to consume water and | carbon sources to do so which on their own would probably be | denser and more effective per unit volume at shielding. Chemistry | has next to nothing to do with radiation shielding let alone | biology. | omginternets wrote: | I imagine this might be interesting for longer distances in | which broken shielding might not be so easily replaced. In such | cases, regenerating your shielding via life-support systems is | a feature, not a bug. | lumost wrote: | Why not fly with a pre pulverized shield? There aren't many | big forces on a long distance space hall and one could | imagine using electrostatic forces to hold the pulverized | shielding in place. No need to regrow the radiation shield | then. | omginternets wrote: | Why not indeed. Why not investigate growing a shield as | well? | ianai wrote: | species: Cladosporium sphaerospermum | | """ | | radiation beneath a [?] 1.7 mm thick lawn of the dematiaceous | radiotrophic fungus was 2.17+-0.25% lower as compared to the | negative control. In addition, a growth advantage in Space of ~ | 21% was observed, substantiating the thesis that the fungus' | radiotropism is extendable to Space radiation. | | """ | ByThyGrace wrote: | So what is "growth advantage" and why is the 21% figure | meaningul? | plutonorm wrote: | The fungus grows better in space. Probably because it's | radiographic (uses radiation for energy). But also possibly | because it came from space and incidentally populates | environments on earth (I'm semi serious). | MauranKilom wrote: | I don't think the conditions on random meteors are in any | way comparable to some lab in the ISS... | ianai wrote: | Consider on the low end ((2.17-.25)% per 1.7 mm thick) this | works out to 88.6 mm for 100% coverage or around 3.5 inches. | | I'm wondering whether the fungus could actually be grown to | various thicknesses, or is 1.7mm kind of its natural thickness? | Might need a layer system of some sort. | | I'm really thinking I should burn some time on learning about | fungi and bacteria. It'd be cool if there were some ecosystem | of them capable of taking in human waste as input and | outputting useful things like cleaner water and shielding. | | (Replied to myself since the other comment is older.) | lioeters wrote: | Book recommendation: Mycelium Running | | > Mycoremediation: the use of mycelium for decomposing toxic | wastes and pollutants | | https://fungi.com/products/mycelium-running | phdelightful wrote: | Does it actually work like that or does each successive 1.7mm | multiply the radiation flux by 0.98? And then the inner | layers will get less radiation and grow less well also? | version_five wrote: | This is correct, each incremental layer would block 2% of | what is incident on it, not knock 2% off the starting | number | ianai wrote: | Yeah if it's like that, I get around .9 meters thick for | blocking 99.999997%. | | I'd like to see what a 10x thicker fungus could block. That | would help inform how it's likely to flesh out at scale. | JohnJamesRambo wrote: | I grew fungi for a living at my previous job. They will grow | in any shape you like as long as they have food and | substrate. | | The lower levels will get less radiation though. | | https://www.buildinggreen.com/blog/greensulate---fungus- | base... | lostlogin wrote: | It could be grown in movable segments so that the less | exposed parts got a good dose regularity. Sounds like a | pain to manage. | | Either way, you'd need to be checking it regularly as | having a section die would be bad. | satya71 wrote: | You'd need about 400mm thick layer to cut radiation to 1% of | incident at 2% per layer. | Voloskaya wrote: | > ((2.17-.25)% per 1.7 mm thick) this works out to 88.6 mm | for 100% coverage or around 3.5 inches. | | 2.17% is when only one side is shielded: "it can be | extrapolated that the biomass would reduce total radiation | levels (of the measured spectrum) by 4.34+-0.5% were it fully | surrounding an object" | | But your assumption that this thing scale linearly is far | from reality, see for example their estimate for Mars: | | "In a case study we estimated that a ~ 2.3 m layer of | melanized fungal biomass (8.6% [wmelanin/wCWW] melanin- | content) would be needed to lower Martian radiation levels to | those on Earth (from 234 mSv/a to 6.2 mSv/a [6, 7, 53])" | | ISS is at apporximately 144 mSv/a. | ianai wrote: | I think it's probably fair to say this is early research | and much more would need to be done. I also figure this | could be done on earth and tested against various radiation | sources. | lostlogin wrote: | > It'd be cool if there were some ecosystem of them capable | of taking in human waste as input and outputting useful | things like cleaner water and shielding. | | Earth is pretty good. A little large to change its direction | of travel though. | yummypaint wrote: | For the record, here is the correct math for attenuation of high | energy photons with a nice explanation from NIST: | https://physics.nist.gov/PhysRefData/XrayMassCoef/chap2.html | | The coefficient in the exponential is 0.0161/mm for these data, | so a 100 mm thick layer will stop 80% of their measured spectrum. | A 200 mm thick layer will stop 96%. | | The same relationship applies for higher energy gammas as well, | but the coefficents will be energy dependent. | kangaroozach wrote: | Encapsulate the entire vessel in a membrane of fungi? No windows | just fungi-bubble deep-space faring? | f6v wrote: | ISS doesn't have that many windows for a reason. | blamestross wrote: | Now this is the solarpunk/biopunk future I signed up for. | Symbiotic radiation shielding fungi for space exploration! | AndrewDucker wrote: | It's a fascinating idea. | | But 2% lower radiation isn't going to do nearly enough. | biorach wrote: | That's with a 1.7mm layer of fungus. This looks to be proof of | concept research. | | Whether thicker layers can be used to provide comprehensive | protection is for future research to establish. (and it's | unlikely to be a linear relationship) | Aspos wrote: | It is 2% with the current strain of the fungus which may evolve | in the future. | ape4 wrote: | When we meet some aliens they might greet the fungus instead of | us | hinkley wrote: | Why have they decorated their ships with dead bodies? What sort | of barbarians are we dealing with here? | MauranKilom wrote: | Decorating the ship with dead fungi would be very pointless | though. You could use most any other material for the same | effect. | f6v wrote: | When we meet some aliens they're likely to be fungus, at best. | kgc wrote: | Where does the additional mass come from when the fungi | reproduces in space? | jxcole wrote: | IIUC most of the mass required to build plants comes out of the | air (CO2). Of course, any astronauts wanting to utilize these | fungi will have to take some amount of other resources with | them. | | The most important measure for any radiation shielding in space | is weight. We have great technology for blocking all radiation | today: lead plating. This is obviously way to heavy for space. | Alternative suggestions have been to surround the astronauts | with water which presents a lot of challenge in terms of | plumbing and weight. Having the walls covered in fungi may | actually be a much lighter option, I certainly hope the idea is | well considered. | hinkley wrote: | The other advantage of fungi might be in the aftermath of a | micrometeoroid event. Does it make more sense to cut a hole | in your shielding and use up a store of fungal bricks that | you brought with you, or to grow a somewhat custom patch with | the right radius of curvature, and slightly larger than the | hole, and then recycling any material that gets removed to | apply the patch. | | If the shield is actually alive (say, a layer around your | emergency shelter), then you can just fill the hole with food | and let the fungi patch themselves, and any damage caused by | being exposed to partial vaccuum. Possibly with a mold that | also acts as a temporary, reusable patch over the worst hit | areas, so that a subsequent space storm doesn't catch you | with your pants down. | meepmorp wrote: | > IIUC most of the mass required to build plants comes out of | the air (CO2). | | Fungi aren't plants, though. | | edit: they're heterotrophs - they get their food from more | complex materials than autotrophs, which generate their raw | material largely from carbon extracted from the atmosphere. | samus wrote: | For fungi, the carbon source is actually even more | straightforward than with plants: we can just feed them | biowaste. Depends on the species of course, and probably | requires some treatment to not encourage growth of less | desirable species instead. If they turn out to be edible, | this could prove to be ideal. | littlestymaar wrote: | > edit: they're heterotrophs | | Except not these ones! These are autotrophs fungi, they do | some kind of photosynthesis (it's absolutely not the same | metabolic path, though) gaining their energy from gamma | rays instead of food. | | Edit: The above comment is wrong, I though autotroph vs | heterotroph was about energy input (as a matter of fact I'm | very convinced it was how my college teacher explained it) | but from wikipedia it looks like I'm wrong, and such fungi | would be classified as Photoheterotroph[1] | | [1]: https://en.wikipedia.org/wiki/Photoheterotroph | meepmorp wrote: | Yes, but they're still fungi. They might be extracting | some amount of energy from radiation, but they still get | most of their energy (and cellular raw material) the old | fashioned, biological way. It's not like they suddenly | evolved replacement pathways to synthesize all the | products they need. | andrewflnr wrote: | Maybe we should think of the fungus as self-managing water | storage and plumbing. | beebmam wrote: | Lead does not block "all radiation". Here's a great video | that explains common types of radiation and what kind of | materials are effective at blocking each of these types of | radiation: https://www.youtube.com/watch?v=iTb_KRG6LXo | | There's plenty of radiation that we have no effective way of | blocking, like neutrino radiation. | hinkley wrote: | Short version: sometimes it's not the bullet that kills you | but the spray or ricochet. There are plenty of types of | radiation that you want to block with light elements. If a | high energy particle spalls off some hydrogen atoms, then | those can be less damaging than a similar collision in | steel or lead. Fungi is a mixture of mostly light elements. | | But that's about the extent of my knowledge. | | Do you happen to know if in a composite shielding situation | (several layers of multiple materials) would you put the | lead on the outside facing the hard radiation, or on the | inside? | formerly_proven wrote: | Ability to block/attenuate radiation is proportional to | interaction probability which is generally also | proportional to biomedical risk: ergo, if we can't block | it, we don't care about it. | lostlogin wrote: | Surely you'd need a lot more water than lead? | | At least you can be using the water though. | samus wrote: | The water will accumulate deuterium and tritium over time | though. Eventually, it will degrade to emergency drink | status. Might be a good way to get at fusion reactor fuel | though. | Tagbert wrote: | Probably water and air. Combine that with the radiation and | trace elements from the water and you have enough to build | tissue. | [deleted] | hinkley wrote: | Imagine you're an interplanetary civilization. You're building | long haul ships not rated for Earth atmosphere, just ferrying | supplies between planets, or landing on moons and asteroids. | You might have a shipyard in orbit, though the moon seems more | likely (too many pulverized metal oxides right there begging to | be dumped into a smelter) or a carbonaceous asteroid (which can | still be high in metals). You can still use vacuum rated | engines to lift it into orbit, although you might have to | design the ship as a second stage for some lifting platform to | get the deltaV you need. | | Growing shielding could be very good. Especially if you can use | waste products to do so. The right sort will be easier to find | on the right asteroid, but could be available on the moon if | you have a high enough volume of imported supplies being turned | into effluent streams. | suifbwish wrote: | Technically light can be converted into mass, but I'm not sure | that's relevant here. | TonyRobbins wrote: | Kyragem wrote: ___________________________________________________________________ (page generated 2022-01-15 23:00 UTC)