Solar Wind—Magnetosphere Coupling During Radial Interplanetary Magnetic Field Conditions: Simultaneous Multi‐Point Observations - Sorbonne Université
Journal Articles Journal of Geophysical Research Space Physics Year : 2021

Solar Wind—Magnetosphere Coupling During Radial Interplanetary Magnetic Field Conditions: Simultaneous Multi‐Point Observations

K.-J. Hwang
N Aunai
R C Fear
H. S Fu
W. Y. Li
C Norgren
T. D. Phan

Abstract

In-situ spacecraft missions are powerful assets to study processes that occur in space plasmas. One of their main limitations, however, is extrapolating such local measurements to the global scales of the system. To overcome this problem at least partially, multi-point measurements can be used. There are several multi-spacecraft missions currently operating in the Earth's magnetosphere, and the simultaneous use of the data collected by them provides new insights into the large-scale properties and evolution of magnetospheric plasma processes. In this work, we focus on studying the Earth's magnetopause (MP) using a conjunction between the Magnetospheric Multiscale and Cluster fleets, when both missions skimmed the MP for several hours at distant locations during radial interplanetary magnetic field (IMF) conditions. The observed MP positions as a function of the evolving solar wind conditions are compared to model predictions of the MP. We observe an inflation of the magnetosphere (∼0.7 RE), consistent with magnetosheath pressure decrease during radial IMF conditions, which is less pronounced on the flank (urn:x-wiley:21699380:media:jgra56856:jgra56856-math-00010.2 RE). There is observational evidence of magnetic reconnection in the subsolar region for the whole encounter, and in the dusk flank for the last portion of the encounter, suggesting that reconnection was extending more than 15 RE. However, reconnection jets were not always observed, suggesting that reconnection was patchy, intermittent or both. Shear flows reduce the reconnection rate up to ∼30% in the dusk flank according to predictions, and the plasma β enhancement in the magnetosheath during radial IMF favors reconnection suppression by the diamagnetic drift.
Fichier principal
Vignette du fichier
2021JA029506.pdf (2.92 Mo) Télécharger le fichier
Origin Publication funded by an institution

Dates and versions

hal-03468620 , version 1 (07-12-2021)

Identifiers

Cite

S Toledo‐redondo, K.-J. Hwang, C P Escoubet, B Lavraud, J Fornieles, et al.. Solar Wind—Magnetosphere Coupling During Radial Interplanetary Magnetic Field Conditions: Simultaneous Multi‐Point Observations. Journal of Geophysical Research Space Physics, 2021, 126 (11), pp.e2021JA029506. ⟨10.1029/2021JA029506⟩. ⟨hal-03468620⟩
56 View
48 Download

Altmetric

Share

More