Year: 2026
Type: article
Abstract: On 2019 October 4, Mars Atmosphere and Volatile EvolutioN (MAVEN) transited through the Martian magnetotail, observing multiple magnetic field reversals in the sunward component. During the second reversal, MAVEN observed wavelike oscillations of the magnetotail current sheet between 17:05 and 17:25 UTC. The oscillations exhibit characteristics of both types of magnetotail flapping waves, large-scale steady flapping of the magnetotail current sheet and propagating kink-like flapping. The average spatial amplitude of the flapping wave is 110.8 ± 20.1 km embedded within the tail current sheet, which has a width of 1096 ± 10.4 km. The characteristic frequency of the flapping waves is 5.3 mHz (period of about 3 minutes) with a width of ±1.3 mHz. Based on the analysis of spacecraft data and accompanying magnetohydrodynamic (MHD) simulations, we suggest that an interplanetary magnetic field (IMF) rotation in the upstream solar wind is consistent with the magnetotail flapping event observed by MAVEN. At the same time as MAVEN observes the magnetotail flapping event, Interior Exploration using Seismic Investigations, Geodesy and Heat Transport (InSight) also records an ultra-low-frequency (ULF) wave event on the surface of Mars with measurements from the InSight Fluxgate Magnetometer (IFG). The characteristic frequency observed by InSight is 5.8 mHz with a width of ±0.4 mHz. Using a simplified Martian ionosphere model, we determine that the nightside ionosphere is too weak to significantly shield the surface from waves in the ULF band. Therefore, we interpret the simultaneous magnetotail flapping waves and ULF waves observed at the Martian surface as having the same origin.
Source: The Planetary Science Journal
DOI: 10.3847/psj/aea140
Authors: Kyle Webster, Yingjuan Ma, Wenyi Sun, Hao Cao
Institutions: University of California System, University of Michigan
Language: English
Subfield: Space and Planetary Science
Field: Earth and Planetary Sciences
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,800
OpenAlex ID: W7215124781