Data from numerous missions reveal that in space, without the protection of our planet’s atmosphere and magnetic field, astronauts can receive in just one day nearly as much cosmic radiation as the average person on Earth accumulates over an entire year.“One day in space is equivalent to the radiation received on Earth for a whole year,” explains physicist Marco Durante, who studies cosmic radiation at the GSI Helmholtz Centre for Heavy Ion Research in Germany.In 2019, he even warned, “As it stands today, we can’t go to Mars due to radiation.
It would be impossible to meet acceptable dose limits.The real problem is the large uncertainty surrounding the risks.We don’t understand space radiation very well and the long-lasting effects are unknown.” This critical challenge has driven the European Space Agency (ESA) to research safer, lighter radiation shields.
Radiation can be a serious hazard for astronauts and the devices they depend on.Powerful streams of high-energy particles come from the Sun during solar flares and from enormous explosions in distant galaxies.While supernovae in our galaxy are rare events, occurring roughly once every half-century, solar flares are much more frequent and can occur several times a day during some solar cycles.
These two events increase cosmic radiation, making space travel more dangerous for astronauts.Without the necessary shielding, electronics could fail, and human health could be in jeopardy.Now, a team of researchers from Ghent University in Belgium is exploring an innovative solution, using 3D printed hydrogels that absorb water to protect astronauts from space radiation.
Space risk: radiation.Image courtesy of ESA.Why Water? Although water could seem like the “unlikely hero” in the fight against cosmic radiation, it is one of the best natural materials for the job.
Water is dense and full of hydrogen atoms.According to the researchers, these hydrogen atoms are very effective at interacting with high-energy particles, slowing them down, and reducing their harmful effects.Basically, water acts like a sponge for radiation, soaking up the dangerous energy that would otherwise harm astronauts.
Still, using water as a radiation shield is not as easy as just carrying around a big water tank.In fact, since water flows freely in its liquid form, trying to pack it into a spacesuit or a spacecraft could end up with bulky containers that make movement difficult.Plus, if the water is not spread out perfectly or even leaks if the container gets punctured, that would be a problem.
In an environment where every ounce counts and a leak could become a disaster for the critical systems in spacesuits and spaceships, the researchers had to think about a different way to solve this hurdle.The breakthrough here was hydrogels, which are formed when superabsorbent polymers (SAPs) soak up water and swell into a gel-like substance.SAPs are used in typical items such as diapers or contact lenses, where they can absorb and retain large amounts of liquid without leaking.
Researchers from the Ghent University Polymer Chemistry and Biomaterials group, led by Professor Peter Dubruel, want to take this technology into space.And thanks to 3D printing, they can shape these hydrogels into almost any form needed for radiation protection.Whether it’s a patch that can be attached to a spacesuit or panels that line the walls of a spacecraft, 3D printing allows for custom geometries.
Postdoctoral researcher Lenny Van Daele, one of the researchers, explains, “The beauty of this project is that we are working with a well-known technology.Hydrogels are found in many things we use every day.Our research group has experience with applications in the medical field – using hydrogels as a soft implantable material to repair damaged tissues and organs.” One big advantage of hydrogels is that they hold water in place instead of letting it flow freely.
The water gets locked inside the material’s structure, spreading out evenly to create consistent radiation protection.Even if a hydrogel patch gets punctured, the water won’t leak out right away.This built-in safety feature gives astronauts extra time to react and fix the issue.
Materials and Process Engineer Malgorzata Holynska from ESA’s Materials, Environments and Contamination Control Section adds, “The material could also potentially be applied to uncrewed missions – in radiation shields for spacecraft, or as water reservoirs, once we have optimized the method of retrieving water from the hydrogel.” This means hydrogels could do two jobs at once: protect astronauts from radiation and store water, which is extremely valuable on long missions.Manon Minsart, a postdoctoral assistant at Ghent University, points out another benefit: “The superabsorbent polymer that we are using can be processed using multiple different techniques, which is a rare and advantageous quality amongst polymers.Our method of choice is 3D printing, which allows us to create a hydrogel in almost any shape we want.
A Step Toward Future Space Missions As plans for human missions to Mars and beyond move forward, the need for lightweight and effective radiation shielding becomes more important.NASA, ESA, and other space agencies have had to balance radiation protection and weight limits since heavier shielding increases launch costs and fuel use.Traditional materials like aluminum and polyethylene offer some protection but add significant mass.
For years, engineers have explored the benefits of using lighter alternatives, like advanced polymers, multi-layered shielding, and even using local materials on the Moon or Mars to keep astronauts and equipment safe without making spacecraft too heavy.Meanwhile, hydrogels offer a lightweight alternative that can be made in different shapes and sizes using 3D printing.Dubruel summed up the goal of their mission: “There is a constant search for lightweight radiation protection materials.
In our Discovery activity, we successfully demonstrated that hydrogels are safe to use under space conditions.In this follow-up project, we are applying different techniques to shape the material into a 3D structure and scale up the production process so that we can come a step closer to industrialization.” Space radiation.Image courtesy of ESA.
Hydrogels could end up being a powerful ally in space.In nuclear reactors and hospitals, water is already used to shield against radiation.The innovation here is in how the water is stored.
By 3D printing water into a solid structure, scientists can use its shielding power without storage or leakage problems in space.The Road Ahead The journey from lab to real-world application is never easy.While the initial tests of 3D printed hydrogels for radiation protection have been promising, more work is still ahead.
Researchers must refine the methods for retrieving water from the hydrogels, perfect the 3D printing process for large-scale production, and test the materials under different space conditions.The team at Ghent University is actively printing hydrogels in their lab, confirming that this research has moved beyond theory and into real-world development.For now, the team has printed hydrogel figures of the space shuttle and an astronaut on the Moon, but their goal is much bigger.
They are using 3D printing to shape hydrogel shields that could be used in astronaut suits, spacecraft, and space habitats on Mars.This approach makes the shields flexible and adaptable, showing that 3D printing is key to making these hydrogels work in space.3D-printed hydrogel space shuttle and astronaut on the Moon.
Image courtesy of ESA/Johan Dubruel.This research is part of a larger effort at Ghent University, where scientists have been working with polymers for medical use since 2006.Their experience with hydrogels in healthcare is now helping them develop radiation shields for space.
ESA is backing this effort, which includes collaborating and actively funding the research.With the help of 3D printed hydrogels, researchers at Ghent University are paving the way for safer space travel, offering a clear path toward future missions, where water could help shield against the inevitable exposure to cosmic radiation.Subscribe to Our Email Newsletter Stay up-to-date on all the latest news from the 3D printing industry and receive information and offers from third party vendors.
