These so-called “convective vortices”, similar to the sand whirlwinds that hit some deserts on Earth, are one of the main atmospheric phenomena on Mars, a dry planet with a very thin atmosphere.
They form when there is a strong temperature difference between the soil and the air, and often get in the way of robotic exploration missions sent by humans. Also, the “Jezero” crater, where the mobile “Perseverance” robot has been operating since February 2021, has witnessed many of these phenomena, but this vehicle manufactured by the US space agency “NASA” has not previously been able to directly monitor its sound.
Fortunately, on September 27, a whirlwind 118 meters high passed over the robot’s head, and its “Supercam” instrument equipped with a microphone recorded the first sound from Mars immediately after its descent.
The data reached Earth a few days later.
In the context, the lead author of the study, whose results were published in Nature Communications magazine, Naomi Murdock, confirmed to Agence France-Presse: “When we realized that we had obtained the images from the camera and also the data of the weather sensors and sound measurement on the site, we felt as if we had won.” Big prize!
The planetary science specialist at the Isai-Supero Institute, in the French city of Toulouse, where the microphone was designed, added: “We hear the wind associated with the whirlwind, the moment it arrives, then everything disappears because we are in the eye of the vortex, then the sound returns again when the microphone passes through the second wall.” ».
Sand Storms
Specifically, the microphone transmitted a precise clicking sound that made it possible to “count the number of particles”, in order to be able to study the structure and behavior of dust.
And Naomi Murdock added, “The dust cycle on Mars and in the sky plays a very important role in relation to the climate, like the water cycle on Earth.”
For his part, the scientific official for the “Supercam” tool, Sylvester Morris, who participated in the study, indicated that the dust analysis makes it possible to “explore the interactions between the Earth and this very soft atmosphere,” which was denser billions of years ago, which allowed the presence of water. liquid on the surface.
This new data would explain how dust is lifted from the surface of Mars, something scientists do not yet know.
Also, Naomi Murdock added, “In some areas, tornadoes pass by, pulling dust and cleaning the solar panels of the robots in their path.”
In other regions, the cyclones pass without raising the dust, for an unknown reason, “and it is just moving air,” as is the case at the site where the American “Insight” probe operates, whose “solar panels are covered with dust,” because it was unable to benefit from the suction devices. This natural.
Elucidating this mechanism may aid in the development of graphic models of ‘dust devils’ to better predict them. On a larger scale, this could make it possible to predict huge dust storms that could cover the entire planet, similar to the scenario of the science fiction movie “The Martian”, which was released in 2015 and described by the scientist as “unrealistic”.
“We are in the process of improving our weather model,” said Sylvester Morris. This is important for the maintenance of our vehicles and for future human exploration missions.”
As for the contribution of these results to research on traces of extraterrestrial life, the physicist pointed out, “One might think that studying the climate of Mars today has nothing to do with searching for traces of life billions of years ago. However, the matter is complementary, because the history of Mars witnessed a severe climate change that made it move from a humid and hot climate, and therefore suitable for the emergence of life, to a completely dry and cold planet.