In situ recording of Mars soundscape

Journal Article · Fri Apr 01 00:00:00 EDT 2022 · Nature (London)

DOI:https://doi.org/10.1038/s41586-022-04679-0· OSTI ID:2523977

Maurice, S. ^[1]; Chide, B.; Murdoch, N.; Lorenz, R. D.; Mimoun, D.; Wiens, R. C.; Stott, A.; Jacob, X.; Bertrand, T.; Montmessin, F.; Lanza, N. L.; Alvarez-Llamas, C.; Angel, S. M.; Aung, M.; Balaram, J.; Beyssac, O.; Cousin, A.; Delory, G.; Forni, O.; Fouchet, T. ; Gasnault, O.; Grip, H.; Hecht, M.; Hoffman, J.; Laserna, J.; Lasue, J.; Maki, J.; McClean, J.; Meslin, P. -Y.; Le Mouélic, S.; Munguira, A.; Newman, C. E.; Rodríguez Manfredi, J. A.; Moros, J.; Ollila, A.; Pilleri, P.; Schröder, S.; de la Torre Juárez, M.; Tzanetos, T.; Stack, K. M.; Farley, K.; Williford, K.; Wiens, R. C.; Acosta-Maeda, T.; Anderson, R. B.; Applin, D. M.; Arana, G.; Bassas-Portus, M.; Beal, R.; Beck, P.; Benzerara, K.; Bernard, S.; Bernardi, P.; Bosak, T.; Bousquet, B.; Brown, A.; Cadu, A.; Caïs, P.; Castro, K.; Clavé, E.; Clegg, S. M.; Cloutis, E.; Connell, S.; Debus, A.; Dehouck, E.; Delapp, D.; Donny, C.; Dorresoundiram, A.; Dromart, G.; Dubois, B.; Fabre, C.; Fau, A.; Fischer, W.; Francis, R.; Frydenvang, J.; Gabriel, T.; Gibbons, E.; Gontijo, I.; Johnson, J. R.; Kalucha, H.; Kelly, E.; Knutsen, E. W.; Lacombe, G.; Le Mouélic, S.; Legett, C.; Leveille, R.; Lewin, E.; Lopez-Reyes, G.; Lorigny, E.; Madariaga, J. M.; Madsen, M.; Madsen, S.; Mandon, L.; Mangold, N.; Mann, M.; Manrique, J. -A.; Martinez-Frias, J.; Mayhew, L. E.; McConnochie, T.; McLennan, S. M.; Melikechi, N.; Meunier, F.; Montagnac, G.; Mousset, V.; Nelson, T.; Newell, R. T.; Parot, Y.; Pilorget, C.; Pinet, P.; Pont, G.; Poulet, F.; Quantin-Nataf, C.; Quertier, B.; Rapin, W.; Reyes-Newell, A.; Robinson, S.; Rochas, L.; Royer, C.; Rull, F.; Sautter, V.; Sharma, S.; Shridar, V.; Sournac, A.; Toplis, M.; Torre-Fdez, I.; Turenne, N.; Udry, A.; Veneranda, M.; Venhaus, D.; Vogt, D.; Willis, P.

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1. Univ. of Toulouse (France); Centre National de la Recherche Scientifique (CNRS) (France); et al.

Before the Perseverance rover landing, the acoustic environment of Mars was unknown. Models predicted that: (1) atmospheric turbulence changes at centimetre scales or smaller at the point where molecular viscosity converts kinetic energy into heat, (2) the speed of sound varies at the surface with frequency and (3) high-frequency waves are strongly attenuated with distance in CO₂. However, theoretical models were uncertain because of a lack of experimental data at low pressure and the difficulty to characterize turbulence or attenuation in a closed environment. Here, using Perseverance microphone recordings, we present the first characterization of the acoustic environment on Mars and pressure fluctuations in the audible range and beyond, from 20 Hz to 50 kHz. We find that atmospheric sounds extend measurements of pressure variations down to 1,000 times smaller scales than ever observed before, showing a dissipative regime extending over five orders of magnitude in energy. Using point sources of sound (Ingenuity rotorcraft, laser-induced sparks), we highlight two distinct values for the speed of sound that are about 10 m s^-1 apart below and above 240 Hz, a unique characteristic of low-pressure CO₂-dominated atmosphere. We also provide the acoustic attenuation with distance above 2 kHz, allowing us to explain the large contribution of the CO₂ vibrational relaxation in the audible range. These results establish a ground truth for the modelling of acoustic processes, which is critical for studies in atmospheres such as those of Mars and Venus.

• Research Organization: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
• Sponsoring Organization: USDOE; USDOE Laboratory Directed Research and Development (LDRD) Program
• Contributing Organization: SuperCam team
• Grant/Contract Number: 89233218CNA000001
• OSTI ID: 2523977
• Alternate ID(s): OSTI ID: 2470470
• Report Number(s): LA-UR--25-21524
• Journal Information: Nature (London), Journal Name: Nature (London) Journal Issue: 7911 Vol. 605; ISSN 0028-0836
• Publisher: Nature Publishing Group
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
Acoustics
Atmosphere
Mars
Microphone
Perseverance
Sound
SuperCam