First Sounds from Mars : Results of the Microphones on Perseverance
- 1JHU Applied Physics Lab, Space Department, Laurel, United States of America (ralph.lorenz@jhuapl.edu)
- *A full list of authors appears at the end of the abstract
While Mars Polar Lander and Phoenix carried microphones, InSight has recorded infrasound, and Huygens and Venera returned some acoustic measurements, Mars 2020/Perseverance is the first planetary mission to return significant amounts of human-audible acoustic data. In addition to the public appeal of planetary sound recordings, these data reveal important aspects of the Martian environment.
Positioned near the top of the rover’s mast, the SuperCam microphone records audible sounds from 20 Hz to 10 kHz. A separate body-fixed microphone is associated with the EDL cameras. Detected sounds originate from three main sources: the atmosphere (turbulence, wind), the crack of the SuperCam laser blasts on rocks, and other rover sounds, such as the high-speed scroll compressor pump on the MOXIE instrument, or the aeroacoustic signal generated by the high-speed rotating blades of the Ingenuity helicopter. These sounds spread over the entire frequency domain accessible by the microphone: (i) the turbulence/wind-induced acoustic signal starts from the lowest frequency, continuously up to few hundred Hz depending on the wind activity. Acoustic power versus frequency shows a decreasing slope consistent with the dissipative regime. (ii) The frequency content of the laser-induced spark lies at higher frequencies (2 - 10 kHz) where it shows destructive interference gaps due to echoes on the mast structure. (iii) Rover generated sounds (MOXIE compressor, rover thermal pump) are monotonic. (iv) Three of the Ingenuity helicopter flights are heard, at the blade’s passing frequency of ~84Hz (with a small Doppler shift due to flight speed) and its first harmonic at 168 Hz.
Passive microphone observations are now made routinely to characterize turbulence, where the observations can access timescales shorter than conventional wind sensors. Similarly, the propagation times of the crack sounds from rapid series of laser shots can interrogate temperature fluctuations on length scales smaller than is possible with conventional temperature sensing. The observations also constrain the acoustic propagation in the Martian atmosphere, where the abundant CO2 causes appreciable attenuation, especially at high frequencies. This presentation will review results to date.
S. Maurice1*, B. Chide2, N. Murdoch3, R. Lorenz4, D. Mimoun3, R. C. Wiens2, A. Stott3, X. Jacob5, T. Bertrand6, F. Montmessin7, N. Lanza2, C. Alvarez Llamas8, S. M. Angel9, M. Aung10, J. Balaram10, O. Beyssac11, G. Delory12, T. Fouchet6, O. Gasnault1, H. Grip10, M. Hecht13, J. Hoffman13, J. Laserna14, J. Lasue1, J. Maki10, J. McClean13, S. Le Mouélic14, A. Munguira Ruiz15, C. E. Newman16, J. A. Rodríguez Manfredi17, J. Moros8, A. Ollila2, P. Pilleri1, S. Schröder18, M. de la Torre Juárez10, T. Tzanetos10, K. Stack10, K. Farley10 1Institut de Recherche en Astrophysique et Planétologie, Université de Toulouse 3 Paul Sabatier, CNRS, CNES, 31400 Toulouse, France. 2Space and Planetary Exploration Team, Los Alamos National Laboratory, Los Alamos, NM 87545, USA. 3Institut Supérieur de l’Aéronautique et de l’Espace (ISAE-SUPAERO), Université de Toulouse, 31400 Toulouse, France. 4Space Exploration Sector, Johns Hopkins Applied Physics Laboratory, Laurel, MD, 20723, USA. 5Institut de Mécanique des Fluides, Univ. Toulouse 3 Paul Sabatier, INP, CNRS. 6Lab. d'Etudes Spatiales et d'Instrumentation en Astrophysique, Obs. Paris, CNRS, Sorbonne Univ., Univ. Paris-Diderot, Meudon, France. 7Laboratoire Atmosphères, Milieux, Observations Spatiales, CNRS, Univ. Saint-Quentin-en-Yvelines, Sorbonne Univ., Guyancourt, France. 8Universidad de Malaga, Malaga, Spain. 9Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC 29208, USA. 10Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA. 11Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, CNRS, Sorbonne Université, MNHN, 75005 Paris, France. 12Heliospace Corporation, Berkeley, CA 94710, USA. 13MIT, Department of Aeronautics and Astronautics, Cambridge, MA, USA. 14Laboratoire de Planétologie de Nantes, CNRS, Univ. Nantes, Nantes, France. 15Escuela de Ingeniería de Bilbao, Universidad del País Vasco UPV/EHU, Bilbao, Spain. 16Aeolis Corporation, Sierra Madre, CA, USA. 17Centro de Astrobiología (INTA-CSIC), Madrid, Spain. 18Institute of Optical Sensor Systems, DLR, Berlin, Germany.
How to cite: Lorenz, R. and the Mars 2020 Acoustics Working Group: First Sounds from Mars : Results of the Microphones on Perseverance, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-1822, https://doi.org/10.5194/egusphere-egu22-1822, 2022.
