By Stephanie Dwilson | 2025-02-27

Radiation exposure poses a significant risk to astronauts venturing beyond Earth's protective magnetic field, but a new breakthrough in 3D-printed hydrogels could provide a game-changing solution.

Researchers at Ghent University in Belgium are developing a hydrogel-based shielding material that could protect both astronauts and space equipment from harmful cosmic radiation.

Hydrogels are superabsorbent polymers (SAPs) capable of holding large amounts of water -- a highly effective material for blocking radiation.

Because future manned missions to the Moon and Mars will expose astronauts to even more space radiation, developing advanced radiation shielding has become an urgent priority.

Water as a shield

Earth's magnetic field acts as a natural barrier against high-energy radiation from space. However, as astronauts travel beyond this protective shield, exposure to galactic cosmic rays, solar particle events and radiation from the Van Allen Belts increases dramatically.

Astronauts aboard the International Space Station (ISS) experience 10 times the radiation levels found on Earth, according to NASA. Future missions to the Moon and Mars will expose crews to even higher doses, heightening the risk of cancer, neurodegenerative diseases and tissue damage.

"In just one week on the ISS, astronauts are exposed to the equivalent of one year's exposure on the ground," the European Space Agency (ESA) said in an undated post on its website.

Given these dangers, developing effective, lightweight and adaptable radiation shielding is a priority for space agencies worldwide.

The team from Ghent University's Polymer Chemistry and Biomaterials Group (PBM) is pioneering the use of 3D-printed hydrogels to address the problem.

Earlier efforts at using water as a shield were clunky. For example, trying to embed spacesuits with containers of water was bulky, limited movement and provided unbalanced protection since the water could move or leak, the ESA said in a February 8 post.

Scaling up production

SAPs offer a better solution. When submerged, they absorb hundreds of times their weight in water. Researchers refer to them as hydrogels when they're in this expanded, bloated state.

By embedding water within hydrogels, researchers eliminate the risk of leakage while maintaining flexibility and structural integrity.

These materials, already used in medical applications such as tissue repair and wound healing, could be adapted for space exploration to coat spacecraft walls, line habitat modules and even enhance spacesuit protection.

Hydrogels could serve "as water reservoirs once we have optimized the method of retrieving water from" them, said Malgorzata Holynska of the ESA's Materials, Environments and Contamination Control Section in the ESA's February 8 post.

By 3D-printing the hydrogels, the team can create them in almost any shape they want, which makes them even more suitable for shielding a variety of different space technologies.

The Ghent University team is now looking at the best way to shape the 3D-printed gels and scale up production.

"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," project lead Peter Dubriel of Ghent University said in the February 8 ESA post.