Inferring the Speed of Sound and Wind in the Nighttime Martian Boundary Layer From Impact‐Generated Infrasound
Abstract The properties of the first kilometers of the Martian atmospheric Planetary Boundary Layer have until now been measured by only a few instruments and probes. InSight offers an opportunity to investigate this region through seismoacoustics. On six occasions, its seismometers recorded short low‐frequency waveforms, with clear dispersion between 0.4 and 4 Hz. These signals are the air‐to‐ground coupling of impact‐generated infrasound, which propagated in an low‐altitude atmospheric waveguide. Their group velocity depends on the structure of effective sound speed in the boundary layer. Here, we conduct a Bayesian inversion of effective sound speed up to 2,000 m altitude using the group velocity measured for events S0981c, S0986c and S1034a. The inverted effective sound speed profiles are in good agreement with estimates provided by the Mars Climate Database. Differences between inverted and modeled profiles can be attributed to a local wind variation in the impact→station direction, of amplitude smaller than 2 m/s.
Authors
- M. Drilleau (ORCID: https://orcid.org/0000-0001-5625-9706)
- Zongbo Xu (ORCID: https://orcid.org/0000-0002-5670-6761)
- Aymeric Spiga (ORCID: https://orcid.org/0000-0002-6776-6268)
- R. García (ORCID: https://orcid.org/0000-0003-1460-6663)
- Taïchi Kawamura (ORCID: https://orcid.org/0000-0001-5246-5561)
- Carène Larmat (ORCID: https://orcid.org/0000-0002-3607-7558)
- É. Beucler (ORCID: https://orcid.org/0000-0003-2605-4990)
- Brent Delbridge (ORCID: https://orcid.org/0000-0003-2808-8772)
- M. Froment (ORCID: https://orcid.org/0000-0002-2980-8711)
- Philippe Lognonné (ORCID: https://orcid.org/0000-0002-1014-920X)
Institutions
- Conservatoire National des Arts et Métiers (FR)
- Centre National de la Recherche Scientifique (FR)
- Los Alamos National Laboratory (US)
- Institut de physique du globe de Paris (FR)
- Université Fédérale de Toulouse Midi-Pyrénées (FR)
- Institut Superieur de l'Aeronautique et de l'Espace (ISAE-SUPAERO) (FR)
- Université Paris Cité (FR)
- Université Nantes Angers Le Mans (FR)
- Sorbonne Université (FR)
- Laboratoire de Météorologie Dynamique (FR)
- Le Mans Université (FR)
- Institut Pierre-Simon Laplace (FR)
- Laboratoire de Planétologie et Géosciences (FR)
- Observatoire des Sciences de l'Univers Nantes Atlantique (FR)
- Norsar (NO)
- Nantes Université (FR)
Publication Details
- Journal
- Geophysical Research Letters
- Published
- 2024-09-10
- DOI
- https://doi.org/10.1029/2024gl109726
- Citations
- 4
- Primary Topic
- Planetary Science and Exploration
- Type
- article
- Field-Weighted Citation Impact
- 1.33
Funders
- Agence Nationale de la Recherche
- Centre National d’Etudes Spatiales