University of Oulu

Pitkänen, T., Kullen, A., Cai, L. et al. Asymmetry in the Earth’s magnetotail neutral sheet rotation due to IMF By sign?. Geosci. Lett. 8, 3 (2021).

Asymmetry in the Earth’s magnetotail neutral sheet rotation due to IMF By sign?

Saved in:
Author: Pitkänen, Timo1,2,3; Kullen, Anita4; Cai, Lei4;
Organizations: 1Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment, Institute of Space Sciences, Shandong University, Weihai, China
2Department of Physics, Umeå University, Umeå, Sweden
3Space Physics and Astronomy Research Unit, University of Oulu, Oulu, Finland
4Space and Plasma Physics, School of Electrical Engineering and Computer Science, Royal Institute of Technology, Stockholm, Sweden
Format: article
Version: published version
Access: open
Online Access: PDF Full Text (PDF, 3 MB)
Persistent link:
Language: English
Published: Springer Nature, 2021
Publish Date: 2021-03-29


Evidence suggests that a non-zero dawn–dusk interplanetary magnetic field (IMF By) can cause a rotation of the cross-tail current sheet/neutral sheet around its axis aligned with the Sun–Earth line in Earth’s magnetotail. We use Geotail, THEMIS and Cluster data to statistically investigate how the rotation of the neutral sheet depends on the sign and magnitude of IMF By. In our dataset, we find that in the tail range of −30< XGSM <−15 RE, the degree of the neutral sheet rotation is clearly smaller, there appears no significant rotation or even, the rotation is clearly to an unexpected direction for negative IMF By, compared to positive IMF By. Comparison to a model by Tsyganenko et al. (2015, doi:10.5194/angeo-33-1-2015) suggests that this asymmetry in the neutral sheet rotation between positive and negative IMF By conditions is too large to be explained only by the currently known factors. The possible cause of the asymmetry remains unclear.

see all

Series: Geoscience letters
ISSN: 2196-4092
ISSN-E: 2196-4092
ISSN-L: 2196-4092
Volume: 8
Issue: 1
Article number: 3
DOI: 10.1186/s40562-020-00171-7
Type of Publication: A1 Journal article – refereed
Field of Science: 115 Astronomy and space science
Funding: The work was supported by the Swedish National Space Agency (SNSA) Grants 118/17 (T.P. and A.K.), 105/14 (A.D.S.), 81/17 (G.S.C.) and 271/14 (M.H.), the National Natural Science Foundation of China (NSFC) Grants 41750110486 (T.P.) and 41850410495 (J.-S.P.) and the Academy of Finland Grant 314664 (H.V.).
Academy of Finland Grant Number: 314664
Detailed Information: 314664 (Academy of Finland Funding decision)
Copyright information: © The Author(s) 2021. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit