Space debris is multiplying, so satellite makers are building better ways to survive a hit

The increasing amount of space debris poses a growing threat to satellites in low Earth orbit, prompting companies to develop new ways to detect and withstand impacts. To address this issue, Odin Space, a California-based firm, has introduced adhesive strips equipped with vibration sensors. These strips record impacts, providing operators with crucial data on the size and force of strikes, which could help clarify the cause of about 60% of small satellite failures within a year of launch, as a 2021 study revealed.

The European Space Agency reports that the volume of human-made material in orbit has more than doubled since 2017, with debris traveling at approximately seven kilometers per second in low Earth orbit. At these speeds, even minor fragments can cause significant damage to electronics, external components, or the satellite itself. Aluminum continues to be the primary material for spacecraft protection, although it offers limited defense against high-speed impacts.

An alternative solution emerges from Atomic-6, based near Atlanta, which is developing Space Armor. This innovation consists of lightweight composite tiles, akin to the size of a hand, 2.5 centimeters thick, and weighing like an iPhone. These tiles are engineered to vaporize metallic debris upon impact, preventing shrapnel formation. Trevor Smith, Space Armor's CEO, explains that this method avoids the mass and space constraints typically associated with conventional shields.

Other researchers are exploring combinations of existing materials. Kevlar, utilized in bullet-resistant gear and aboard the International Space Station, can be paired with Nextel, a woven ceramic material, to create a lighter shield for smaller, more cost-effective spacecraft. Meanwhile, researchers at the University of Padua in Italy are utilizing 3D printing techniques to craft experimental shields from aluminum, Kevlar, and carbon-fiber-reinforced resin, enabling intricate void structures that could effectively break up incoming projectiles, similar to a Whipple shield.

NASA has also tested aluminum foam as a shielding material, finding that a shield with an aluminum-foam layer around 6 millimeters thick offers protection comparable to a conventional Whipple shield that is twice as heavy. The optimal solution will depend on the specific operational orbit of a satellite, as debris can comprise metal fragments, plastics, paint flecks, and natural rocks, with varying compositions across different orbits.

Shielding designers like Rannveig Marie Faergestad at Thales Alenia Space emphasize the importance of gathering precise impact data to inform engineers on selecting the most suitable materials and shield designs.