Summary
NASA’s Perseverance rover measured fine and ultrafine Martian dust clinging to samples of spacesuit materials carried on the rover. The results could help guide spacesuit, habitat and dust-removal designs for future Mars crews.
NASA’s Perseverance rover has detected fine and ultrafine Martian dust clinging to samples of spacesuit materials carried on the rover. Measurements made over 1,645 Martian days include particles about 100 to 300 nanometres across on some surfaces. The findings, which NASA says are published in the Proceedings of the National Academy of Sciences on Oct. 27, could help inform spacesuit and habitat design, dust-removal procedures and health standards for future Mars missions.
What Perseverance measured
The rover carries five small spacesuit-material samples, each 20 millimetres square, on calibration targets for two instruments. NASA sent the samples to study how suit materials hold up on the Martian surface. The instruments also provided a way to examine dust that settled on the materials.
PIXL, an X-ray spectrometer, measured dust on a Teflon sample and basaltic glass. Because PIXL cannot directly detect elements in Teflon, the elemental signals from that target came from dust resting on it. The team also examined Teflon and Vectran swatches on SHERLOC’s calibration target.
PIXL detected fine particles smaller than 2.5 micrometres and ultrafine particles around 100 nanometres. Dust on PIXL’s Teflon target and SHERLOC’s Vectran swatch averaged about 2 micrometres. On PIXL’s basaltic glass and SHERLOC’s Teflon swatch, particle sizes ranged down to about 100 to 300 nanometres. These measurements describe dust attached to calibration-target surfaces, rather than the amount of dust a crew would breathe in a habitat or during an outdoor activity.
The team found that the materials collected different particle sizes, with static electricity appearing to influence which grains stuck to which surfaces. The finest particles remained attached through years of rover driving and drilling. PIXL also found dust enriched in phosphorus and detected signs of calcium sulfate; the dust’s iron- and sulfur-rich composition matched earlier measurements.
Why particle size matters for crews
On Earth, particles smaller than 2.5 micrometres can penetrate deep into the lungs and enter the bloodstream. NASA also notes that studies of ultrafine particles have shown they can travel from the nasal cavity to the brain along the olfactory nerve. Martian dust is predominantly made of silicate minerals and can contain reactive compounds, including perchlorates and reactive iron. NASA says the health risks for crews will depend on how much dust they encounter and how long they are exposed.
The measurements give engineers and flight surgeons information about how dust accumulates on candidate suit materials. NASA says that differences in how materials hold dust could guide future material and protective-coating choices. The results may also inform designs such as suitports, where a suit attaches to the outside of a habitat, and dual-chamber airlocks intended to limit dust entering living spaces.
Perseverance’s main mission is to search for signs of ancient microbial life, but NASA also designed it to help prepare for human exploration. The dust measurements add surface data to that work, alongside technology demonstrations such as the Mars Oxygen In-Situ Resource Utilization Experiment and Ingenuity.