Three Martian dust devils can be seen near the rim of Jezero Crater in this short video made of images taken by a navigation camera aboard NASA’s Perseverance rover on Sept. 6, 2025. The microphone on the rover’s SuperCam previously captured audio when a dust devil passed over.
NASA/JPL-Caltech/SSI
Perseverance confirmed a long-suspected phenomenon in which electrical
discharges and their associated shock waves can be born within Red Planet
mini-twisters.
NASA’s Perseverance Mars rover has
recorded the sounds of electrical discharges —sparks — and mini-sonic booms in
dust devils on Mars. Long theorized, the phenomenon has now been confirmed
through audio and electromagnetic recordings captured by the rover’s SuperCam
microphone. The discovery, published Nov. 26 in the journal Nature, has implications
for Martian atmospheric chemistry, climate, and habitability, and could help
inform the design of future robotic and human missions to Mars.
A frequent occurrence on the Red
Planet, dust devils form from rising and rotating columns of warm air. Air near
the planet’s surface becomes heated by contact with the warmer ground and rises
through the denser, cooler air above. As other air moves along the surface to
take the place of the rising warmer air, it begins to rotate. When the incoming
air rises into the column, it picks up speed like spinning ice skaters bringing
their arms closer to their body. The air rushing in also picks up dust, and a
dust devil is born.
SuperCam has recorded 55 distinct
electrical events over the course of the mission, beginning on the mission’s
215thMartian day, or sol, in 2021. Sixteen have been recorded when dust devils
passed directly over the rover.
Decades before Perseverance landed,
scientists theorized that the friction generated by tiny dust grains swirling
and rubbing against each other in Martian dust devils could generate enough of
an electrical charge to eventually produce electrical arcs. Called the
triboelectric effect, it’s the phenomenon at play when someone walks over a
carpet in socks and then touches a metal doorknob, generating a spark. In fact,
that is about the same level of discharge as what a Martian dust devil might
produce.
“Triboelectric charging of sand and
snow particles is well documented on Earth, particularly in desert regions, but
it rarely results in actual electrical discharges,” said Baptiste Chide, a
member of the Perseverance science team and a planetary scientist at L’Institut
de Recherche en Astrophysique et Planétologie in France. “On Mars, the thin
atmosphere makes the phenomenon far more likely, as the amount of charge
required to generate sparks is much lower than what is required in Earth’s
near-surface atmosphere.”
Perseverance’s SuperCam instrument carries a microphone to analyze the sounds of the instrument’s laser
when it zaps rocks, but the team has also captured the sounds of wind and even
the first audio recording of a Martian dust devil. Scientists knew it could pick up
electromagnetic disturbance (static) and sounds of electrical discharges in the
atmosphere. What they didn’t know was if such events happened frequently
enough, or if the rover would ever be close enough, to record one. Then they
began to assess data amassed over the mission, and it didn’t take long to find
the telltale sounds of electrical activity.
The SuperCam microphone on NASA’s Perseverance
captured this recording of the sounds of electrical discharge as a dust devil
passed over the Mars rover on Oct. 12, 2024. The three crackles can be heard in
between the sounds of the dust devil’s front and trailing walls.
Credit: NASA/JPL-Caltech/LANL/CNES/CNRS/ISAE-Supaero
Crackle, pop
“We got some good ones where you
can clearly hear the ‘snap’ sound of the spark,” said coauthor Ralph Lorenz, a
Perseverance scientist at the Johns Hopkins Applied Physics Lab in Laurel,
Maryland. “In the Sol 215 dust devil recording, you can hear not only the
electrical sound, but also the wall of the dust devil moving over the rover.
And in the Sol 1,296 dust devil, you hear all that plus some of the particles
impacting the microphone.”
Thirty-five other discharges were
associated with the passage of convective fronts during regional dust storms.
These fronts feature intense turbulence that favor triboelectric charging and
charge separation, which occurs when two objects touch, transfer electrons, and
separate — the part of the triboelectric effect that results in a spark of
static electricity.
Researchers found electrical discharges did not seem to increase during the seasons when dust storms, which globally increase the presence of atmospheric dust, are more common on Mars. This result suggests that electrical buildup is more closely tied to the localized, turbulent lifting of sand and dust rather than high dust density alone.
While exploring the rim of Jezero Crater on Mars,
NASA’s Perseverance rover captured new images of multiple dust devils in
January 2025. These captivating phenomena have been documented for decades by
the agency’s Red Planet robotic explorers.
Credit: NASA/JPL-Caltech/LANL/CNES/CNRS/INTA-CSIC/Space Science
Institute/ISAE-Supaero/University of Arizona
Profound effects
The proof of these electrical
discharges is a discovery that dramatically changes our understanding of Mars.
Their presence means that the Martian atmosphere can become sufficiently
charged to activate chemical reactions, leading to the creation of highly
oxidizing compounds, such as chlorates and perchlorates. These strong
substances can effectively destroy organic molecules (which constitute some of
the components of life) on the surface and break down many atmospheric
compounds, completely altering the overall chemical balance of the Martian
atmosphere.
This discovery could also explain
the puzzling ability of Martian methane to vanish rapidly, offering a crucial
piece of the puzzle for understanding the constraints life may have faced and,
therefore, the planet’s potential to be habitable.
Given the omnipresence of dust on
Mars, the presence of electrical charges generated by particles rubbing
together would seem likely to influence dust transport on Mars as well. How
dust travels on Mars plays a central role in the planet’s climate but remains
poorly understood.
Confirming the presence of electrostatic discharges will also help NASA understand potential risks to the electronic equipment of current robotic missions. That no adverse electrostatic discharge effects have been reported in several decades of Mars surface operations may attest to careful spacecraft grounding practices. The findings could also inform safety measures developed for future astronauts exploring the Red Planet.
Source: NASA Rover Detects Electric Sparks in Mars Dust Devils, Storms - NASA
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