Articles | Volume 31, issue 5
Ann. Geophys., 31, 817–833, 2013
Ann. Geophys., 31, 817–833, 2013

Regular paper 06 May 2013

Regular paper | 06 May 2013

Comparative magnetotail flapping: an overview of selected events at Earth, Jupiter and Saturn

M. Volwerk1, N. André2,3, C. S. Arridge4,5, C. M. Jackman5,6, X. Jia7, S. E. Milan8, A. Radioti9, M. F. Vogt10, A. P. Walsh4,*, R. Nakamura1, A. Masters11, and C. Forsyth4 M. Volwerk et al.
  • 1Space Research Institute, Austrian Academy of Sciences, Graz, Austria
  • 2Centre d'Etude Spatiale des Rayonnements, Université de Toulouse, UPS, Toulouse, France
  • 3CNRS, UMR 5187, Toulouse, France
  • 4Mullard Space Science Laboratory, University College London, Holmbury St. Mary, UK
  • 5Centre for Planetary Sciences at UCL/Birkbeck, London, WC1E 6BT, UK
  • 6Department of Physics and Astronomy, University College London, Gower Place, London, WC1E 6BT, UK
  • 7Dept. of Atmospheric, Oceanic and Space Sciences, University of Michigan, Ann Arbor, USA
  • 8Department of Physics and Astronomy, University of Leicester, Leicester, UK
  • 9Laboratoire de Physique Atmosphérique et Planétaire, Institut d'Astrophysique et de Géophysique, Université de Liège, Liège, Belgium
  • 10Department of Physics and Astronomy, University of Leicester, Leicester, UK
  • 11Institute of Space and Astronautical Science, JAXA, Sagamihara, Japan
  • *now at: Science and Robotic Exploration Directorate, ESA/ESTEC, Noordwijk, the Netherlands

Abstract. A comparison of magnetotail flapping (the up-and-down wavy motion) between the Earth and the two giant planets Jupiter and Saturn has been performed through investigation of the current sheet normal of the magnetotail. Magnetotail flapping is commonly observed in the Earth's magnetotail. Due to single spacecraft missions at the giant planets, the normal is determined through minimum variance analysis of magnetometer data during multiple intervals when the spacecraft crossed through the current sheet. It is shown that indeed a case can be made that magnetotail flapping also occurs at Jupiter and Saturn. Calculations of the wave period using generic magnetotail models show that the observed periods are much shorter than their theoretical estimates, and that this discrepancy can be caused by unknown input parameters for the tail models (e.g., current sheet thickness) and by possible Doppler shifting of the waves in the spacecraft frame through the fast rotation of the giant planets.