One of the challenges of recording sounds on Mars is that because the atmosphere is so sparse there, scientists were not sure if it would be possible to record sounds at all. The atmosphere consists mainly of carbon dioxide, which also tends to absorb sound waves. So the fact that the microphones in Perseverance were able to record Ingenuity from a distance of 80 meters was a surprise and a pleasure. But this means that the recordings that are available tend to be silent. “Mars is very quiet due to the low atmospheric pressure,” the co-author of the Baptiste Chide study at the Los Alamos National Laboratory in New Mexico said in a statement. “But the pressure changes with the seasons on Mars.” This means that we can expect changes to the sounds being recorded in the future. “We are entering a time of high pressure,” Chide said. “Maybe the acoustic environment on Mars is less quiet than it was when we landed.” The strangest finding from the study is that the speed of sound on Mars is variable. Here on Earth, the speed of sound is 767 mph. But on Mars, the speed at which sound travels depends on its height: low-pitched sounds travel at about 537 mph, and higher-pitched sounds travel much faster at 559 mph. This seems to be due to the extreme nature of the delicate, cold atmosphere. The recordings were made using Perseverance’s two microphones: one on the SuperCam instrument, used to hear the sounds produced when a laser strikes its rock target for spectroscopy, and a second to record the puff sounds of the instrument. Gas Dust Removal. cleans the rock surfaces from debris. The SuperCam microphone is the main one used for scientific work. NASA / JPL-Caltech “The microphone is now used many times a day and performs extremely well. “Its overall performance is better than we’ve modeled and tested even in a Mars-like environment on Earth,” said David Mimoun, a professor at the Institut Supérieur de l’Aéronautique et de l’Espace (ISAE-SUPAERO). and team leader. who developed the microphone experiment. “We could even record the roar of the Mars helicopter over a long distance.” Sustainability of sound research on Mars opens up new avenues of research. “It’s a new sense of research we’ve never used before on Mars,” said Sylvestre Maurice, an astrophysicist at the University of Toulouse in France and lead author of the study. “I expect a lot of discoveries to be made, using the atmosphere as a source of sound and as a means of dissemination.”

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