Skip to Main content Skip to Navigation
Journal articles

One-Hertz Waves at Mars: MAVEN Observations

Abstract : We perform a survey of 1-Hz waves at Mars utilizing Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft observations for a Martian year. We find that the 1-Hz wave occurrence rate shows an apparent variation caused by masking of the waves by background turbulence during the times when the background turbulence levels are high. To correct for this turbulence masking, we select waves that occur in time intervals where the background turbulence levels are low. We find that the extreme ultraviolet flux does not affect the wave occurrence rate significantly, suggesting that the newly born pickup ions originating in the Mars's exosphere contribute minimally to the 1-Hz wave generation. We find that the wave occurrence rates are higher for low Mach numbers and low beta values than for high Mach numbers and high beta values. Further, we find that a high percentage of 1-Hz waves satisfy the group-standing condition, which suggests that a high percentage of the waves seen as monochromatic waves in the spacecraft frame can be broadband waves in the solar wind frame that have group velocities nearly equal and opposite to the solar wind velocity. We infer that the wave occurrence rate trends with the Mach number and proton beta are a consequence of how the Mach numbers and beta values influence the wave generation and damping or how those parameters affect the group-standing condition. Finally, we find that the 1-Hz waves are equally likely to be found in both the quasi-parallel and the quasi-perpendicular foreshock regions.
Document type :
Journal articles
Complete list of metadata

https://hal-insu.archives-ouvertes.fr/insu-03678217
Contributor : Nathalie POTHIER Connect in order to contact the contributor
Submitted on : Wednesday, May 25, 2022 - 1:17:52 PM
Last modification on : Wednesday, June 1, 2022 - 4:20:10 AM

File

JGR Space Physics - 2018 - Ruh...
Publisher files allowed on an open archive

Licence

Copyright

Identifiers

Collections

Citation

Suranga Ruhunusiri, J. S. Halekas, J. R. Espley, F. Eparvier, D. Brain, et al.. One-Hertz Waves at Mars: MAVEN Observations. Journal of Geophysical Research: Space Physics, 2018, 123, pp.3460-3476. ⟨10.1029/2017JA024618⟩. ⟨insu-03678217⟩

Share

Metrics

Record views

0

Files downloads

0