SuperCam’s Microphone Records a Martian Dust Devil
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This video and audio show the results of NASA’s Perseverance Mars rover using its SuperCam microphone to record the sounds of a Martian dust devil – the first time any such recording has been made. The dust devil passed by on Sept. 27, 2021, the 215th Martian day, or sol, of the mission. The dust devil was estimated to be 82 feet (25 meters) wide, at least 387 feet (118 meters) tall, and moving at about 12 miles per hour (19 kilometers per hour).
At the same time that SuperCam’s microphone recorded the dust devil, Perseverance’s weather sensors (measuring wind, pressure, temperature, and dust) and the Navigation camera (Navcam) were on. This allowed scientists to combine sound, image, and atmospheric data. The unique combination of these data, along with atmospheric modeling, allowed the researchers to estimate the dust devil’s dimensions.
Capturing a passing dust devil takes some luck. Scientists can’t predict when they’ll pass by, so rovers like Perseverance and Curiosity routinely monitor in all directions for them. As scientists see them occur more frequently at a certain time of day, or approaching from a certain direction, they’ll focus their monitoring to try and catch a dust devil.
The video included here shows three rows. The top row is a raw image taken by Navcam of the Martian surface; while the camera is capable of color, it takes black-and-white images when searching for dust devils to reduce the amount of data sent back to Earth (most of the images come back without a dust devil detected).
The middle row shows the same image processed with change detection software to indicate where movement occurred as time passed by; color is used to show density of dust, going from blue (noise to low density dust) through purple to yellow. The last row is a graph showing a sudden drop in air pressure recorded by Perseverance’s weather sensor suite, called Mars Environmental Dynamics Analyzer, provided by Centro de Astrobiología (CAB) at the Instituto Nacional de Tecnica Aeroespacial in Madrid and the sound amplitude from SuperCam’s microphone.