Ranking the drivers of the Martian bow shock location: a statistical analysis of Mars Atmosphere and Volatile EvolutioN and Mars Express observations
- 1IRAP, Université de Toulouse, CNES, CNRS, UPS, (Toulouse), France (philippe.garnier@irap.omp.eu)
- 2ISAE-SUPAERO, Université de Toulouse, 10 Avenue Edouard Belin, 31055 Toulouse, France
- 3Laboratory for Atmospheric and Space Physics University of Colorado, Boulder, US
- 4Department of Astronomy, University of Maryland, College Park, MD, US
- 5NASA Goddard Space Flight Center, Greenbelt, MD, US
- 6School of Physics and Astronomy, University of Leicester, Leicester, UK
- 7Department of Physics and Astronomy, University of Iowa, Iowa City, Iowa, USA
The Martian interaction with the solar wind leads to the formation of a bow shock upstream of the planet. The shock dynamics appears complex, due to the combined influence of external (solar photons, solar wind plasma and fields) and internal (crustal magnetic fields, ionized atmosphere) drivers. The extreme ultraviolet fluxes and magnetosonic mach number are known major drivers of the shock location, while the influence of other possible drivers is less constrained or unknown such as crustal magnetic fields or the solar wind dynamic pressure and the Interplanetary Magnetic Field (IMF) intensity and orientation.
We analyze and rank the influence of the main drivers of the Martian shock location, based on published datasets from Mars Express and Mars Atmosphere Volatile EvolutioN missions and on several methods such as the Akaike Information Criterion, Least Absolute Shrinkage Selection Operator regression, and partial correlations. We include here the influence of the crustal fields, extreme ultraviolet fluxes, magnetosonic mach number, solar wind dynamic pressure and various Interplanetary Magnetic Field parameters (intensity and orientation angles).
We conclude that the major drivers of the shock location are extreme ultraviolet fluxes and magnetosonic mach number, while crustal fields and solar wind dynamic pressure are secondary drivers at a similar level. The IMF orientation also plays a significant role, with larger distances for perpendicular shocks rather than parallel shocks.
How to cite: Garnier, P., Jacquey, C., Gendre, X., Génot, V., Mazelle, C., Fang, X., Gruesbeck, J., Sanchez-Cano, B., and Halekas, J.: Ranking the drivers of the Martian bow shock location: a statistical analysis of Mars Atmosphere and Volatile EvolutioN and Mars Express observations, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-1609, https://doi.org/10.5194/egusphere-egu22-1609, 2022.
