Evidence of lightning on Mars, detected in sounds and electrical signals captured by NASA’s Perseverance rover, is presented in a paper published in Nature. The observations indicate that Mars’s atmosphere is electrically active, informing our understanding of the planet’s atmospheric chemistry and may have implications for future exploration.

In our Solar System, lightning and electrical activity occur on Earth, Saturn, and Jupiter. The existence of electrical activity on Mars has been theorized, but never directly demonstrated. Mars’s dusty surface frequently hosts a range of localized and planet-wide events, including wind-blown dust and sand, dust storms, and dust devils, that are known to cause electrification on Earth. Understanding whether such electrification occurs on Mars is critical because it informs our understanding of the surface chemistry of the planet and could affect the safety of robotic and human missions.

To answer this question, Baptiste Chide and colleagues analyse 28 hours of microphone recordings, taken from Perseverance over two Martian years. By identifying interference and acoustic signatures that are characteristic of lightning, the authors categorize 55 electrical events. They found that 54 of the events occurred within the top 30% of the strongest wind events recorded during the study period, indicating that wind plays a crucial role in initiating electrical charge on Mars. Sixteen events were also recorded during the rover’s only two close encounters with dust devils, highlighting the possibility that more distant, or low-energy discharges, could have also taken place beyond the microphone’s range.

These observations suggest that Mars’s atmosphere is electrically active, particularly during localized dust lifting rather than during globally dusty seasons. The authors note that such activity could enhance oxidizing conditions, affecting organic preservation and habitability, and may pose risks to equipment and astronauts. They call for dedicated instruments and improved atmospheric models to quantify electrical phenomena and their chemical consequences on Mars.