Dust devils are conspicuous swirls of dust that appear and disappear on Mars. As with tornadoes on Earth, a dust devil is created by an upward rotating column of hot air. When the column spins fast enough, it picks up small dust grains from the ground, making the vortex visible.
Dust devils have already been sighted on Mars on other occasions, but this is the first time that their sound has also been heard, thanks to a microphone from Perseverance, a NASA robotic rover that circulates on the surface of the Red Planet. since landing on it two years ago.
Recording sounds on Mars does not give the same results as recording them on Earth. Many things on Earth whose sounds are familiar to us would not sound the same on the Red Planet.
Because the Martian atmosphere is much less dense than our planet’s, this affects the way sound waves travel from the source to the microphone. Sounds tend to be weaker on Mars.
On the other hand, since the atmosphere of Mars is made up mostly of carbon dioxide (Earth’s atmosphere is made up mostly of nitrogen and oxygen), high-pitched noises on Mars are more attenuated than low-pitched ones. That makes the low tones dominate over the highs almost all the time.
The audio captured by the microphone of the SuperCam, a scientific instrument whose development was led by the US National Laboratory of Los Alamos, and the images captured at the same time by the Navcam camera, show that the dust eddy measured more than 118 meters in diameter. high and 25 meters in diameter. At the same time, the MEDA instrument, a meteorological station developed in Spain under the direction of the Center for Astrobiology (CAB), dependent on the Higher Council for Scientific Research (CSIC) and the National Institute of Aerospace Technology (INTA), made measurements of the pressure of the air.
From top to bottom: the place where the dust devil passed, the dust devil highlighted at a distance of between 50 and 60 meters in a processed photo, the atmospheric pressure, and finally, a graph of the sound captured when the dust devil Dust passed over the Perseverance. (Images: NASA JPL / Caltech / LANL / CNES / CNRS / CAB / INTA / CSIC / Space Science Institute / ISAE / SUPAERO)
Baptiste Chide’s team, from Los Alamos National Laboratory, examined the images, sounds and other data of the dust devil’s passage over Perseverance, verifying, among other things, that the sound of the eddy is heard in the audio and also that of grains of sand hitting the robot.
In this link the audio recording accompanied synchronously by images of changes in the audio graph and changes in atmospheric pressure can be downloaded in MP4 format.
The study is titled “The sound of a Martian dust devil”. And it has been published in the academic journal Nature Communications. (Fountain: NCYT de Amazings)