Summary
NASA’s Perseverance rover detected fine and ultrafine Martian dust clinging to spacesuit-material samples carried on board. The measurements could help guide ways to limit dust exposure during future crewed missions.
NASA’s Perseverance rover has detected fine and ultrafine Martian dust clinging to samples of spacesuit materials carried on board. The measurements, collected over 1,645 Martian days, are the first on-site measurements of these particle sizes on Mars, according to NASA’s Jet Propulsion Laboratory. The findings were scheduled for publication in Proceedings of the National Academy of Sciences on October 27, 2026.
The samples were mounted on calibration targets for instruments on the rover’s robotic arm. Their dust measurements could help inform spacesuit and habitat design, dust-removal procedures and health standards for future Mars missions.
How Perseverance measured the dust
The rover carries five small spacesuit-material swatches, each three-quarters of an inch (20 millimetres) square. They are part of a calibration target for SHERLOC, an instrument that studies materials using Raman spectroscopy and luminescence. NASA sent the samples to Mars to study how spacesuit materials hold up on the surface.
A second instrument, PIXL, measures the chemical composition of materials using X-rays. Its calibration target includes Teflon and basaltic glass. Because Teflon contains no elements PIXL can directly detect, elemental signals from that sample can be attributed to dust resting on it.
PIXL detected fine particles smaller than 2.5 micrometres and ultrafine particles around 100 nanometres. A human hair is about 70 micrometres wide. Dust on PIXL’s Teflon target and SHERLOC’s Vectran swatch averaged about 2 micrometres. On the basaltic-glass sample and SHERLOC’s Teflon swatch, particle sizes reached roughly 100 to 300 nanometres.
The measurements also showed that different materials collected different particle sizes. NASA’s team says static electricity appears to influence which particles stick to which surfaces: dust grains become charged through collisions in the air, and materials attract them differently. The finest particles remained attached through years of rover driving and drilling. The dust’s chemistry matched earlier findings of iron- and sulfur-rich material; PIXL also found phosphorus enrichment and signs of calcium sulfate.
Why particle size matters for future crews
Fine particles can penetrate deep into the lungs, and some can enter the bloodstream. Research on Earth has linked particulate matter below 2.5 micrometres to health effects; studies have also found that ultrafine particles can travel from the nasal cavity towards the brain along the olfactory nerve. Martian dust includes chemically reactive compounds, such as perchlorates and reactive iron, that could pose additional concerns. The health risk would depend on how much dust people encounter and for how long.
The measurements concern dust deposited on material samples, rather than the amount suspended in the air around a crew. They therefore provide information about how dust interacts with suit materials, not a direct measure of astronauts’ inhaled exposure.
NASA says the results could help engineers compare suit materials and protective coatings, and plan ways to keep dust out of habitats. Designs such as suitports, which allow astronauts to enter a suit attached outside a habitat, and dual-chamber airlocks are among the approaches that could reduce dust brought into living areas. Martian grains are less abrasive than lunar dust, but their small size and chemical properties make controlling them an important part of planning for surface exploration.