NASA's Perseverance rover has detected electric discharges in Martian dust devils for the first time, revealing crackling electricity in the planet's atmosphere. These sparks, captured by the rover's microphone, arise from colliding dust grains and could explain rapid methane loss on Mars. The discovery highlights risks to future missions and new insights into the planet's chemistry and climate.
Dust storms on Mars, which frequently whip up swirling dust devils, have long been known to lift fine particles into the air. However, recent analysis of audio from NASA's Perseverance rover shows these whirlwinds also produce tiny electric sparks. The microphone on the SuperCam instrument, the first ever deployed on Mars, recorded unusual signals during two dust events. Scientists from French research institutions, including the Institut de recherche en astrophysique et planétologie, identified these as electromagnetic and acoustic signals from electric discharges.
The process mirrors static electricity on Earth but occurs more readily on Mars due to its thin carbon dioxide atmosphere, requiring less charge to ignite sparks. Dust grains collide and rub, building up electrical charges that release as short arcs, just a few centimeters long. These bursts create audible shock waves, similar to mild static shocks felt in dry conditions.
This finding, published in Nature in 2025, has significant implications for Martian science. The discharges enable the formation of oxidizing compounds that can degrade organic molecules and alter atmospheric chemistry. Researchers suggest these reactions might account for the puzzling quick disappearance of methane, detected sporadically but vanishing faster than models predict.
Beyond chemistry, the electricity could influence dust transport, affecting weather patterns and climate dynamics on Mars, which remain incompletely understood. For space exploration, the sparks pose potential threats: they might disrupt electronics in robotic probes or endanger astronauts in future human missions.
The SuperCam microphone began operating in 2021, shortly after Perseverance's landing, and has since amassed over 30 hours of recordings, including wind sounds and helicopter noises. This audio breakthrough demonstrates how acoustic data can reveal invisible atmospheric processes on distant worlds.
