This artist concept shows electrical discharges within Martian dust storms.
Credit: NASA
Scientists have confirmed that, within the swirling dust storms common on Mars’ surface, small electrical discharges occur as the fine particles rid themselves of built-up static by rubbing against one another. This confirms that the Martian atmosphere can form highly oxidizing compounds, which could explain why the planet’s surface seems so devoid of organic material, which it once featured in abundance.
Mars has had detectable dust storms for many years, but they’ve been observable from much closer with the Perseverance rover’s SuperCam instrument. Using its microphone, it recorded the first sounds from Mars in 2021 and, to date, has recorded over 30 hours of audio from the Red Planet. While recording, a pair of small dust devils passed the rover, allowing Perseverance to capture strong signals from within the clouds of dust and debris.
A Martian dust devil captured by the Curiosity rover in 2020.
Credit: NASA
Analyses carried out by scientists at the University of Toulouse and the University of Versailles showed that these signals were actually electric discharges. The studies, published in Nature, showed how small static shocks—like those we experience here on Earth—were being generated by the friction between dust particles within the clouds, resulting in small arcs of electricity.
On one hand, this is profoundly cool: It’s the first recording of an electrical discharge of this kind on another planet’s surface. But it’s the potential shit in our understanding of the Martian atmosphere that is potentially more intriguing. These findings demonstrate that the Martian atmosphere can reach sufficient charge levels to generate highly oxidizing compounds. Since such substances can destroy organic molecules and other atmospheric compounds, that could explain why Mars’ surface appears so barren, and why there’s so little methane in the atmosphere.
It also raises warnings for current and future spacecraft heading to Mars, as those electrical discharges could affect sensitive equipment operating within dust storms. Future manned missions will need to factor this into their safety and technical assessments of how to approach surface landings and extended-stay missions.