Dust storms on Mars are one of the most famous features of the red planet, and one of the main obstacles that robotic vehicles (rovers) exploring it have to face due to the damage it can cause to their electronic equipment. Now, one of these robots, Perseverance, has demonstrated for the first time that lightning also occurs on Mars. Until now, it was believed that there was electrical activity in the Martian atmosphere, but no evidence had been found.
The study's results are published this Wednesday in the journal Nature.
Mars now joins the group of Solar System countries where lightning is generated and there is electrical activity, as this phenomenon occurs on Earth, Saturn, and Jupiter. The finding by Perseverance, the robot launched by NASA in 2020, was not a surprise as the dusty Martian surface experiences localized atmospheric events from time to time that cause electrification, such as wind carrying dust and sand, dust storms, and dust devils.
Understanding if this electrical activity also occurred on Mars, the authors say, was crucial to understanding the chemical composition of the red planet's surface and the implications it could have on Martian missions, both robotic and manned, as it can affect astronaut safety.
To clarify this issue, the team led by Baptiste Chide, from the Institute of Astrophysics and Planetary Research in Toulouse (France), analyzed 28 hours of recordings that Perseverance collected with its microphones over two Martian years (equivalent to four Earth years). By identifying interferences and acoustic signatures characteristic of lightning, the authors classified 55 episodes with electrical activity.
Their analysis revealed that wind plays a crucial role in generating electrical charge on Mars. They also observed that the Martian atmosphere shows electrical activity especially during localized dust uplift, rather than during global dust seasons.
On August 20, 2024, NASA's rover was engulfed in a dust storm, allowing scientists to study how a phenomenon like this forms and evolves on Mars with the robot's instruments. In 2018, a global dust storm affected much of the red planet and was documented by the Curiosity rover.