Aluminum Eggshells Could One Day Help Protect Spacecraft From Dangerous Space Debris

Ninety years after the first moon landing, humanity continues to venture further into space. In 2026, notable missions such as Artemis II and the Nancy Grace Roman Space Telescope were launched, yet this surge in spacecraft launches has resulted in an accumulation of debris in low Earth orbit (LEO). Currently, over a million pieces of debris larger than one centimeter orbit in LEO, posing a risk of high-speed impacts as more spacecraft are launched.

In response to this issue, researchers at Dalian University of Technology in China have turned to the humble eggshell for inspiration.

The study, published in the Journal of Applied Physics, suggests that aluminum eggshells filled with water could serve as a protective barrier for spacecraft. Natural biological structures, such as eggs, have evolved to absorb and distribute energy efficiently over time. The team created a metastructure consisting of multiple aluminum "eggshells" with water inside, placed between two aluminum impact plates.

The idea was that, upon impact, the energy would be dispersed among the "eggs," slowing it down and preventing damage to the spacecraft.

The researchers conducted simulations to test this concept. They compared water-filled aluminum eggshells to empty aluminum plates and found that the water-filled eggs significantly outperformed the other options. The water-filled aluminum eggs withstood high impacts and reduced the impact projectile by nearly 65 percent, compared to a 51 percent reduction for the empty aluminum plates.

Further testing revealed that placing the aluminum eggs upright, with their small end touching the top of the plate, resulted in the best overall performance.

While the concept is promising, further research is needed to optimize the design, geometry, thickness, and filling requirements of the aluminum eggshells. Researchers hope that this bio-inspired approach to space debris protection will attract more attention and lead to advancements in the field, ultimately safeguarding future spacecraft from the dangers of space debris.