MycoShell
The flagship grown shield. Read the full product page.
Overview
Why every space habitat needs radiation shielding.
Outside Earth's magnetic field and atmosphere, a habitat is exposed to galactic cosmic rays, solar particle events and secondary radiation produced when those particles strike the structure itself. Over a long mission the cumulative dose can exceed what is considered acceptable for a career.
The conventional answer is mass: put enough dense material between the crew and the radiation. For Mars-surface radiation, NASA and ISS modelling points to about 2.3 metres of solid shielding material, far too heavy to launch. The best shielding is therefore material already at the destination, and this is where in-situ resource utilization comes in.
Aeginis takes the idea one step further: instead of only piling up regolith, grow a shell from it with a radiotrophic fungus whose melanin absorbs and converts radiation. The rest of this page covers each destination in turn.
Radiation
Mars round trip versus NASA's proposed career limit
One Mars mission delivers about 68% more than NASA's proposed career limit. Source: Curiosity RAD instrument; National Academies space radiation report.
Moon
Moon base and lunar habitat shielding.
The Moon has no atmosphere and no global magnetic field, so a surface habitat is exposed to the full space radiation environment, plus a punishing temperature swing between lunar day and night. Artemis-era surface missions and Gateway-linked modules are moving from design into hardware.
Lunar regolith is plentiful, which makes it the natural shielding material. Options include covering a habitat with regolith, sintering it into blocks, or binding it biologically. A grown fungal-regolith composite ships as a flat scaffold and expands on site, and the same biology doubles as structure and as a water and waste filter.
Mars
Mars habitat shielding and structure.
Mars has a thin atmosphere that offers some protection but not enough: a full round trip delivers about 1.01 Sv, and the surface still carries a significant dose. The Mars surface also adds a chemical hazard: very fine dust containing 0.5 to 1% perchlorate, which interferes with thyroid function.
A fungal-regolith composite is attractive on Mars because the regolith and water are local. NASA-tested myco-composite cut proton radiation by more than 99% at 3 inches, and modelling projects a roughly 1 m fungal-regolith composite could bring Mars-surface dose to Earth-normal levels.
To scale
How thick does a shield need to be?
Both figures are modelling results from different studies (NASA/ISS modelling; bioRxiv 2020), drawn to scale and not a like-for-like test.
Jupiter system
Jupiter, Europa and Ganymede radiation.
Jupiter's powerful magnetosphere traps charged particles in intense radiation belts. Moons such as Europa and Ganymede orbit inside them, which makes the Jovian system one of the most radiation-hostile destinations in the solar system and a long-term challenge for any crewed outpost or orbiter.
We treat Jupiter-system shielding as a research concept: the same radiotrophic biology and regolith approach is a candidate, but it needs dedicated modelling and testing, and we make no flight claims for it.
Beyond Mars
Wherever there is regolith, there is a place to grow a shield.
3 worldsMoon, Mars, Jupiter system
Comparison
Approaches to habitat shielding.
| Approach | Launch mass | Role in radiation protection | Maturity |
|---|---|---|---|
| Solid shielding (metal, polyethylene) | High: everything is launched | Predictable, proven, but heavy | Flight-proven |
| Regolith piled, bagged or sintered | Low: local material | Uses local mass; no biological function | Ground-tested concepts |
| Grown fungal-regolith composite (MycoShell) | Low: ships flat, grows on site | Mass from regolith plus radiotrophic melanin; also structure and filtration | TRL 4, system integration underway |
Learn more
Go deeper.
Technology
How radiotrophic fungi, melanin and regolith combine. See the process.
Science
Sources, evidence and the research timeline. Read the evidence.
Questions
Space habitat FAQ.
How do you protect astronauts from radiation on Mars?
Mars has a thin atmosphere and no global magnetic field, so the surface is exposed to galactic cosmic rays and solar particles. Protection comes from putting mass between the crew and the radiation. Because launching that mass is very costly, the approach we are developing, MycoShell, grows a radiation-shielding shell on site from local regolith and a radiotrophic fungal strain.
Can fungi be used to build space habitats?
Yes, as a research direction. NASA's myco-architecture programme, in NIAC Phase III, is testing grown mycelium composites for off-world habitats, and a melanized fungus flown to the ISS attenuated radiation. Aeginis is engineering these two threads into one product.
What is a space habitat?
A space habitat is a pressurised, shielded structure where people live and work off Earth, such as a lunar surface base, a Mars surface habitat or a commercial station module. It must provide air, water, structure, thermal control and protection from radiation and micrometeoroids.
How much radiation would astronauts receive on a Mars mission?
Measurements by Curiosity's RAD instrument indicate about 1.01 sieverts cumulative dose on a full Mars round trip, above NASA's proposed 600 millisievert career limit.
Is Jupiter's radiation a problem for habitats?
Jupiter's magnetosphere traps charged particles in intense radiation belts, making the environment around moons such as Europa and Ganymede among the harshest in the solar system. Any outpost or orbiter there would need far stronger shielding. Our Jupiter-system work is at concept and research stage and makes no flight claims.
What is in-situ resource utilization (ISRU)?
ISRU means using materials found at the destination, such as lunar or Martian regolith and water, instead of launching everything from Earth. Growing a shield from regolith is an ISRU approach.
Is MycoShell ready for a mission?
No. MycoShell is at technology readiness level 4: component-level laboratory and flight data exist and system integration is underway. Our roadmap runs from coupon tests through an ISS demonstration to a station-module pilot.
Let's build the next shield together.
Space agencies, station builders, research institutes and sustainable-construction partners: we would like to hear from you.