Electric Currents in Geospace and Beyond

Andreas Keiling, University of California, Berkeley, USA Octav Marghitu, Institute of Space Sciences, Romania Michael Wheatland, University of Sydney, Australia

Dedication v

Contributors ix

Preface xiii

Part I: Introduction

1 Pioneers of Electric Currents in Geospace 3
Asgeir Brekke

2 Current Systems in Planetary Magnetospheres: A Comparative Overview 17
Krishan K. Khurana and Jiang Liu

3 Electric Currents in the Solar Atmosphere 43
Gregory D. Fleishman and Alexei A. Pevtsov

4 Multipoint Analysis of Electric Currents in Geospace Using the Curlometer Technique 67
M. W. Dunlop, S. Haaland, X‐C. Dong, H. R. Middleton, C. P. Escoubet, Y.-Y. Yang, Q.-H. Zhang, J‐K. Shi, and C. T. Russell

5 Inferring Currents from the Zeeman Effect at the Solar Surface 81
Graham Barnes and K. D. Leka

Part II: Ring Currents

6 ENA Imaging of Planetary Ring Currents 95
P. C. Brandt, S. Y. Hsieh, R. DeMajistre, and D. G. Mitchell

7 Terrestrial Ring Current: A Review of Cluster Results Based on the Curlometer Technique 115
I. Dandouras, S. Rochel‐Grimald, C. Vallat, and M. W. Dunlop

8 The Nature of Jupiter’s Magnetodisk Current System 127
N. Achilleos

9 The Ring Current of Saturn 139
N. Sergis, E. J. Bunce, J. F. Carbary, S. W. H. Cowley, X. Jia, D. C. Hamilton, S. M. Krimigis, D. G. Mitchell, and M. K. Dougherty

Part III: Current Sheets

10 Review on the Characteristics of the Current Sheet in the Earth’s Magnetotail 157
A. T. Y. Lui

11 Recent Advances Regarding the Mars Magnetotail Current Sheet 177
Michael W. Liemohn and Shaosui Xu

12 Current Sheets at the Giant Planets 191
Christopher S. Arridge and Carley J. Martin

13 Planetary Magnetopause and Heliopause Current Sheets 207
E. S. Belenkaya

14 MHS Models of Current Layers in the Solar Atmosphere 219
Clare E. Parnell

15 Large‐Scale Current Sheets in Flares and CMEs 239
Jun Lin and Lei Ni

Part IV: Field‐Aligned Currents

16 A Review of Birkeland Current Research Using AMPERE 259
John C. Coxon, Stephen E. Milan, and Brian J. Anderson

17 Birkeland Currents at Mercury: Review and Comparison With Earth 279
Brian J. Anderson, Catherine L. Johnson, Haje Korth, and Lydia C. Philpott

18 Recent Advances in the Study of Upward Field‐aligned Currents Generated Near the Earth’s Magnetopause Boundary 303
Simon Wing, Jay R. Johnson, and Marius Echim

19 The Current System of Dipolarizing Flux Bundles and Their Role as Wedgelets in the Substorm Current Wedge 323
Jiang Liu, V. Angelopoulos, Zhonghua Yao, Xiangning Chu, Xu‐Zhi Zhou, and A. Runov

20 Cusp Current System: An Energy Source View 339
M. Yamauchi and R. Slapak

21 Magnetospheric and Atmospheric Controls of Giant Planet Auroral Currents 359
L. C. Ray

22 The Ambivalent Role of Field‐Aligned Electric Currents in the Solar Atmosphere 371
Manolis K. Georgoulis

23 Solar Active Region Electric Currents Before and During Eruptive Flares 391
B. Schmieder and G. Aulanier

Part V: Ionospheric Currents

24 Review of Data Analysis Techniques for Estimating Ionospheric Currents Based on MIRACLE and Satellite Observations 409
H. Vanhamäki and L. Juusola

25 Earth’s Ionosphere: Theory and Phenomenology of Cowling Channels 427
Akimasa Yoshikawa and Ryoichi Fujii

26 Ionospheric Currents at Mars and Their Electrodynamic Effects 445
Matthew Fillingim

27 Ionospheric Currents due to Ionosphere‐Magnetosphere Coupling at Jupiter and Saturn 459
G. J. Hunt, S. W. H. Cowley, and J. D. Nichols

Part VI: Other Current Systems

28 The Bow Shock Current System 479
Ramon E. Lopez

29 Current Systems of Inert Moons 497
M. Holmström and S. Fatemi

30 Currents in Cometary Comae 513
Martin Volwerk

Index 535